Hi! Sorry for the long update! I think I haven't given Y/N much of a spotlight, have I?
Here's the next chap! Please wait for her appearance in the book!
Uhm, beware of cursing from some classmates of ours :)
——————Somewhere in the woods on the mountain of class 3-E—————
3rd person's POV 
Koro-sensei was sitting on a gazebo, relaxed. On one of his tentacles there was a newspaper and another one was holding a glass of tropical fruit juice with a straw decorated with a violet flower. He was reading the newspaper.
  "Even America only talks about the moon. I was hoping for something more interesting on the first page, but it seems..."
Before the beginning of class, he would always relax in the woods behind the classroom... A dark-blue-haired boy thought as he looked at Koro-sensei from behind a tree. With a glass of juice and an English newspaper he got from Hawaii, with his Mach 20 speed....
  "Exactly like what you've written in your note. Thanks, Nagisa." The boy turned to Nagisa, who was actually behind him with notes in his hand.
  "Yeah, 頑張ってるよ (ganbatteru yo), Sugino." Nagisa nodded while giving Sugino an encouraging smile.
  "Of course!" Sugino gave him his confident smile while raising a baseball with BBs sticking on it. "Ten billion yen would be mine!" He then stood back, raising his left leg while holding the ball with two hands, getting into his favorite stance.
We are killers, and our target is sensei. Was what Nagisa thought when watching his friend throw the ball.
  Sugino threw the ball with force and a very good aim. It went straight for the teacher's unsuspected head.
  "Good morning, the two of you." He said, now sanding behind Nagisa. The two boy were shocked, Sugino still in his throwing position.
  "Alright, give your teacher a big welcome!" He raises his tentacle hand on a greeting manner.
  "E-Ehh?!"  Sugino stood up and looked bewildered at the now destroyed gazebo, then back at Koro-sensei, then to the gazebo again. While Nagisa absentmindedly greeted him back, "G-Good morning, Koro-sensei."
"Sticking BBs used to kill me on a baseball? What a great idea. When you do that, it won't make noises, unlike guns." Koro-sensei explained, "However, until when the ball reaches me, I have plenty of leisure time. And because my cells will be cut when they touch the BBs directly, I've passed the equipment room and took this glove from it." He said as he raised his tentacle hand. It was covered with a baseball glove and there the ball was, still smoking from the impact.
"Ehhh!?!" Nagisa and Sugino could only gaped at the teacher.
His face had green stripes on it, again. "I hope you can kill me... before graduation." He said confidently while absentmindedly toying with the BBs baseball with his gloved hand.
"Now, it's time for class to begin," Koro-sensei announced as he walked toward their class with his head the normal yellow color and gloved hand holding the baseball.
"Yes sir..." Sugino trailed off as he hung his head low, shoulder dropped as he had failed to kill his teacher with his best plan. Nagisa looked at him in both concern and sympathy. "Damn it, maybe my throwing technique really isn't that good after all."
"Sugino..." Nagisa called his friend softly. He was looking at the ground with gloomy eyes, his face pessimistic.
———————Class 3-E———————
Nagisa's POV
Our teacher has blown up 70% of the moon. He said next March he would do that to the Earth as well. For unknown reasons, this creature wanted to be our teacher. The mission that the Ministry of Defense gave us was: to "assassinate" him before next March. The reward was ten billion yen!
"Ne, Nagisa!" Kaede called me. "Has Sugino's plan to kill the teacher failed?" "Yeah," I answered her while glancing at Sugino, "after that he seems quite upset about it." He still looked gloomy, with his right hand clenched up.
"It's not a big thing to be upset at. I mean, until now, no one in our class succeeded in doing so."
I looked at Koro-sensei, who was writing on the board. An unkillable teacher: Korosenai Sensei. And that becomes his nickname, Koro-sensei.
Third person's POV
Suddenly, tentacle went pass Nagisa, missing him by an inch. It grabbed something looked like a notebook and went up again. This happens just in a few seconds.
"Sugaya-kun!" Said student jumped and flinched, both confused and scared to realize that his notebook, which he had been drawing on, was snatched away by none other than his "model", Koro-sensei.
He looked at his teacher, who was looking at the picture with glinted eyes, for fear of being given a detention for not giving his attention in class. But...
"Almost correct! Although some recognizable features of mine are somewhat better than this." Koro-sensei gave his review to the astonished student, whilst turning his notebook to the class. The teacher had obviously drew red lines in his notebook to fix his drawing. "Better?! Where?!" Sugaya was pissed off. Koro-sensei's head isn't that thin!
The school bell rang. "That's all for today." Koro-sensei said to the class who were all packing, "today I have some business to do so I'll see you all tomorrow!" "Business?" Isogai asked, confused. "Yes, I need to watch a match in NY." He answered as he opened the window and sped up to the sky, leaving yet again some smoke and the class shielding with hands.
"He's gone." Taisei frowned as he lowered his shielding hands. "Really," Terasaka tsked, "what is he?"
  Hinano said as she was looking at the class schedule for tomorrow, "it would be great if  he brings back a few souvenirs for us." She rearranged the books in her bag.
  "No one takes souvenirs from their assassination target, right?" Meg assured her. "It's ok if it's food." Hinano answered her in a cheerful tone, "because once we've eaten, there's nothing left." Meg only sweat dropped. "You're realistic in a weird way."
  "Souvenirs from NY? What could it be?" Isogai asked his friend as this was obviously heard by the boys. "Wine?" Maehara teased him. "We can't drink that." Isogai grinned.
  "Sweets are best after all, right?" Hinano exclaimed as she heard the conversation between the boys.
"Or a blonde beauty," Okajima said as he drooled, thinking of one. He put his hands toward his chest and started his weird obsession dance.
"True true," said Maehara when he helplessly agreed.
"Blonde, blonde, blonde,..." Okajima continues the obsession dance. While Nagisa can only smiled as he walked towards the front door. He was having none of it, as he saw Karasuma there instead.
"Oh, Karasuma-san." Isogai greeted him, which made the class turned to the newcomers.
"How was it? Did you find a clue on how to kill him?" He ask, going straight to the problem as the serious and straightforward person he is.
"Clue?" Nagisa repeated as he looked at Karasuma. The class was avoiding him, looking away in shame. Some looked down, some looked out the window, some scratched their necks whereas others looked at him in confusion. "Hmm, I mean... we are class E." Hazama Kirara the creepy girl said as she put her hands behind her head. "It's really not possible, Karasuma-san." Isogai admitted as he looked at Karasuma in anxiety.
"The teacher is too fast," Koki tiredly answered as he laid down the desk. "How can we kill a creature that could fly with the speed of Mach 20?"
"That's true, there's no army that could keep up with that speed." Karasuma agreed.
"Really?" Okajima asked in concern. "Yes. Only you class have the chance. For whatever reasons, he insisted on his teaching your class."
The scene changes to NY, with a player in a baseball match swing the bat, and sent the ball to the sky, as Koro-sensei - disguised - was watching and eating popcorn whilst ignoring the weird looks people gave him.
"If this is left alone, next March he will blow up the Earth. You should've understood when you look at the blown up moon. Next March, humanity won't be saved no more. It's too dangerous to let him live. This class is the only place where he could be killed." Karasuma said seriously with his brows knitted and his eyes sharp.
Our class was given the chance to become the heroes who save the Earth. Nagisa thought. But, I really don't get it. Why did he want to destroy the Earth? Why, at that time, did he want to teach us?
—————Next day's Lunchtime—————
Everyone was chatting or eating their lunch quietly in the classroom, it was loud, but comfortable. But Sugino wasn't there. Closing the lid and putting down his barely eaten bento, he sighed. He looked down to the ground below the staircase he was sitting on.
"I've done cleaning it, Sugino-kun." A tentacle covered with a white handkerchief gave him the BBs baseball he had thrown in attempt of killing Koro-sensei. He looked back, "Koro-sensei... But wait, what are you eating?" His question was directed to a big hard greenish nut-lookalike thing on the teacher's other tentacle. "A coconut I bought from Hawaii yesterday." He answered as he took another bite, including the outside of the coconut. "You want a bite?" Isogai took the baseball on the teacher's tentacle as he turned the offer down, "normally it is a type of drink, sensei."
"Nice throw yesterday, don't you think?" Said Koro-sensei as he sparked up a conversation. He took another big bite of the poor coconut.
"Easy for you to say. Not like I can ever hit you at Mach 20 with my throwing speed." Sugino said matter-of-factly.
"Are you in the baseball club?" Koro-sensei looked at him as he gave his question. Sugino returned the gaze, but looked at the ground shortly after, his face gloomy again. "I used to be." "Used to?" "The clubs... every club prohibited anyone in class E to participate. Our bad grades got us here, so we're supposed to focus on studying." He explained.
"That's some nasty discrimination." Koro-sensei gave his opinion.
"It's alright. You saw yesterday, right?" Sugino assured him in a pessimistic way, "how slow I am? In the end, I couldn't pitch a single strike, so I got benched. Wasn't long before I lost interest in studying too, and wound up in the ol' End class."
"Sugino-kun?" Koro-sensei called him, his face dangerously close. "Let me give you a little advice." He said as his eyes gleamed.
—————————————————
  "Gotta turn this in." Nagisa was walking towards the staff room when he saw Koro-sensei sitting with Sugino outside. "Koro-sensei... talking to Sugino? About what?" He suddenly remembers something. "Is he giving a talking to about yesterday's attempt?" With that, he waisted no time to run to the door.
  "Wow, he's really up in arms!"  Once outside, Nagisa saw Koro-sensei strangling, or what he thought it is, Sugino with his tentacles. He immediately run towards the strangling duo. "Koro-sensei! What are you doing? What happened to your pledge not to hurt your students?"
"Nurufufufu" the octopoid teacher just laughed, "Sugino-kun?" There came a muffled sound from the student in his tentacles. "That unusual pitching form I saw yesterday... you're copying major-league pitcher Arita, aren't you?" Koro-sensei asked him. His eyes widens and sweat started to pour from his face. "But you know, tentacles don't lie. Your shoulder muscles are out of whack compared to Arita's." "What's that supposed to mean?" Sugino asked, suspicion rising. "You won't be able to pitch his super fastballs with that body, no matter how much you try to imitate him." The sentence was like a knife that stabbed Sugino hard. Nagisa flinched as he heard those menacing words that were oh-so-familiar to him, being in class 3-E.
  "How?" Nagisa stepped up as bangs covered his eyes. "How can you be so sure?" "Nagisa?" Sugino hesitantly called as he saw the other's trembling fists and the face he was making. "Because we're misfits? Because we're the End class?" He looked up, his eyes looked so desperate but determined. "So we shouldn't bother?! Is that it?!" He fueled as he took it all out on the teacher. Sugino, after hearing that, only lowered his head and look away.
  "Hmm, well..." Koro-sensei hummed calmly. "How do I know it's impossible, you ask?" He took something from his sleeve. It was a newspaper with the title "Tentacles Attack!". He was back to his cheerful tone, "why, I checked the man himself yesterday!"
  In the front page was an image of Arita, being held exactly the same as Sugino, by tentacles coming from nowhere in the ground. Nagisa and Sugino literally jaw-dropped and utterly speechless. Well then, never mind!  "I even got his autograph!" Koro-sensei raised the autograph the reads "Keep your tentacles to yourself! -Arita" while comical crocodile tears were coming from his beady eyes. "You asked him for an autograph after that?! No wonder he was furious!" Nagisa managed to find back his words as he threw that sentence to the octopoid superbeing. "I just couldn't believe my tentacles!" He retorted back. Nagisa sighed as he lifted his hand on his forehead.
  "I get it. I just don't have his talent." Sugino, all the while sitting on the ground, said in relief. "Uhm." Nagisa agreed with him. "On the other hand," a tentacle reached towards Sugino, "your elbows and wrists are more flexible then Arita's." Said Koro-sensei ad the tentacles reached Sugino's wrist and elbow. He encouraged, as the other was looking at the wrist that was gripped gently by the teacher, "train well, and you could far surpass him. When I'm fondling for research purpose, my tentacles are never wrong." He put another tentacle on the other's shoulder, "there's more than one kind of talent." He then turned away, leaving Sugino behind with a surprised look, "find an assassination style that suit yours."
  "My elbows and wrists... are better?" Sugino said in awe as he touched his wrist. "My... talent?" He bent his wrist quite gentle with a loving smile.
  Nagisa turned towards the teacher who was walking to class, and sent his direction a gentle smile. A bird landed on the octopoid teacher's academic hat. He snapped from his daze, and caught up with the teacher.
  "Koro-sensei!" The yellow teacher, who was going to open the classroom door, turned back, only to see his blue-haired student running up to him. "Did you go to New York just to give Sugino advice?" Nagisa asked as he handed the teacher his assignment.
  "Of course. I'm his teacher." Koro-sensei answered him. "But most teachers wouldn't go anywhere near that far." The blue-haired teen gave his reason. "But you will? The guy who's going to destroy the Earth?"
  A scene flashed in the yellow octopoid superbeing's mind. A destroyed building, and a woman laying there, blu coat stained with blood.
  "Nagisa-kun," he pointed his fingers to himself, "I become a teacher to keep a promise I made." He took the assignment from the student's hand, and checked it with Mach 20 speed. "And while I do intend to destroy Earth, I'm your teacher first and foremost. Taking you kids is seriously more important than the end of the world." He said as he showed his student the checked assignment with the comment "No major mistakes and a great ending! A fantastic diary entry!" and a 96 on the higher left side, a flower on the higher right, and lots of other small comments, plus his confession: "I like sushi, too! My favorite ingredient is botan-ebi."
  "Koro-sensei..." the teen took his work from the teacher's tentacle hand and felt touched inside. Until he finished his sentence, that is.
  "...stop giving me extra questions! I know that you have Mach 20 speed! No need to show off!"
The teacher panicked, "but I thought you like bonus questions? They can earn you bonus points!"
  Nagisa was literally speechless as he looked at the question: "State in English why this tentacle can't sprout well." with a tentacle having a cute pink bow on its top, "I think they are more like punishments."
  Koro-sensei hadn't got out of his panic state just yet, "So, er, I hope you students will take your education and my assassination just as seriously." Green stripes started to form as he swiveled the red pen skillfully in the air with only one tentacle finger and took a bite from it, "not that I ever expect you to pull of the latter."
  Nagisa stared at the teacher enjoying his red pen by rapidly taking bites from it. He gave a helpless tiny smile, while Koro-sensei kept on munching the pen as if it's the best food in the whole world.
—————Later that day, outside——————
  Sugino got in his stance, and throw the ball with the best he got. Nagisa, who was the one to catch it, could only dodge as the baseball flew towards him with a "whoosh" and landed on the higher land behind him. "Uwah!"
  "Wow, Sugino! That broke so fast it practically disappeared for a while!" He praised him as he threw the ball back to his friend, the latter caught it effortlessly.
  "Eheheh!" Sugino gave out a proud but shy laugh. "I'm working on a curveball that puts my elbows and wrists to good use! Even my slow fastball will look speedy when I mix up the two!" His face turned grim, "I'm sure they'd both just put him to sleep, though." He quickly regains his usual determined self. "But I'll hang in there, Nagisa. I won't give up on baseball or assassination!" He throws the ball back to his friend, and Nagisa caught it with a smile and nodded "uhm!"
He looked at the ball in his hand. Our teacher moves incredibly fast, and his tentacles can do all kinds of things. Honestly, I don't think we can kill him. The one mentioned was checking tests, making homework's, making tests, and even eating with insane speed.p inside the staff room. And yet...
"Koro-sensei!" Sugino peered in the window and called the teacher. He turned, his tentacle hands stopped, revealing a black pen and a red pen in their grasps. "Hmm?" Sugino immediately invited him, like a talk between friends, "Can you come over here? I wanna try killing you for a bit." He pointed his thumb back outside, where Nagisa stood, behind him. The teacher snickered with green stripes all over his head, "still haven't learnt your lesson, huh?" He teased the cheerful student, as he left, leaving a test with the name Tomohito Sugino, 32/50 was the score, and a flower with a comment next: "Your score has gone up a bit. Congrats!"
...being taught by Koro-sensei is strangely motivating, and being in his assassination classroom... is kind of fun.
—————————————————
Koro-sensei is having a peaceful time. He was sitting on a picnic mat, and was grating ice he got from the Arctic with a cute penguin grater. His eyes look calm and his form relaxed, nothing could ruin his day. At least, that's what he thought.
"There he is!" A female voice whispered under the bushes, it was Meg. "He said he'd be snacking on some North Pole snow cones today." A male voice whispered back, Maehara. Koki huffed in an annoyed tone, "that octopus, hittin' the North Pole like it's the corner shop!" Isogai announced quietly to the others behind him. "It's time! We split the ten billion!" "Hm!" The others replied huskily, revealing Meg, Maehara, Koki, Yada Toka - a brunette, and Okano Hinata - a short-violet-haired female.
"Koro-sensei!" The one mentioned look up, to see his students all running up to him, smiling widely and waving their hands. Sunlight peered through the leaves just make the scene more endearing. "Can we have snow cones too?"
Koro-sensei had happy tears streaming from his eyes, his yellow cheeks tinted pink adorably, looking at his beloved students. They've opened their hearts to me— with such smiling faces!
They pulled out their knives from behind, and still with a cheerful look on their faces, raised their hands with the knives, preparing to stab him.
How ferocious they must be! was Koro-sensei's remaining thought. He dried his teary eyes with a handkerchief and then dodged, all done with insane speed that caused smokes and covered the students' sights.
When the amateur assassins' sight have cleared, all they saw left was the penguin grater lying innocently on the ground.
"But you know..." They all lifted their heads, to see Koro-sensei behind them. "Your smiles were a little forced. That was hardly enough for me to let down my guard." He was back-facing them with his head turned back, on one of his tentacles was a beautiful snow cone. "Set aside these dangerous anti-sensei knives," he said as he raised his other tentacle hand, revealing a fabric carrying something,he dropped it down to let them see the rubber knives, "stop and smell the flowers, and learn how to smile less maliciously before you try again." The teens all looked down to see the tulips in their hands, exactly the position they held their knives in. Meg figured out something.
"Hey, Koro-sensei!" She yelled at him while pointing at the flower. "These are the flowers we have been growing!" He immediately panicked. "Yaa! I-Is that so?" The scene glimpsed at the small patch of tulips besides the class, now only holes on the ground.
"That's low, Koro-sensei!" Yada said while covering her mouth with her free hand, while Hinata is (fake, in my opinion) crying. "After we took such good care of then and they'd finally bloomed..." That made the teacher panicked even more. He waved his tentacles around desperately while sweating continuously. "Apologies! I'll get you some new bulbs right now!" He went to Finland, collected them, and went back in seconds, so fast they would've thought he was there all the time if not for the smoke. "Here they are!"
  And now, he was planting tulips with his students on watch. "Don't go planting them with Mach speed, okay?"  Hinata commanded. "Understood!" He said in panic, and sweats came out even more as he planted the bulbs. "Handle each one gently!" Meg ordered as she crossed her arms in irritation. "Got it!" He answered and continued his work.
"Hey, isn't he planning to destroy the Earth?" Two boys in the background, Maehara and Isogai, stood helplessly staring at the desperate teacher's back. "Y-Yeah, and here he is, planting tulips." Isogai answered his friend as both sweat dropped.
But unlike those boys who were smiling at the scene, a certain student, with his gang and another girl who were all hiding behind the equipment room, was irritated. "Tch. The monster's tryin' ta be all goody-two-shoes.l
"What are you writing, Nagisa?" Kaede asked as they, too, were standing beside of the classroom. "I thought I'd jot down Koro-sensei's weak points." He smiled at the greenette. "They might clue me in to a good assassination method." "Hmm?" Kaede peered at the note: Koro-sensei's weak point #1: things get shaky when he shows off. "And that's supposed to be helpful?" Nagisa couldn't respond to this as he tilted his head, his eyes half-lidded, and silently wondering why he added it.
"Don't be like that," Sugino's wristband hand took the note from the blunette's hand. "This stuff could come in super handy!" He read another page aloud. "'Height: about 3 meters if standing on his tip-tentacles. Special moves: supersonic speed'—" he stopped reading. "Nanikore? (The hell is this?)" he stared at the sentence as Nagisa looked at him with an I-told-you-already look. "So... not useful then." Kaede said kinda helplessly. "Not right now." Nagisa responded as he gave a close-eye smile. We are killers. Class 3-E at Kunugigaoka Junior High School is the assassination classroom, and the other students are elite members of a prestigious prep school.
——————Main Campus——————
"I believe the Ministry of Defense has already informed you, but as of tomorrow, I'll be joining class E as their P.E and assistant homeroom teacher. I'll be keeping an eye on him, of course, but I'll also be providing the students with the technical and mental support they need. Never fear: I have a teaching certificate." Karasuma announced to the principal. "Go right ahead. Just remember: their education and safety comes first." The principal gave his permission with a low tone. "If you'll excuse us." Karasuma said politely, then left.
"What an understanding principal." Karasuma's assistant praised the principal as they walked in the hallway. "The government is compensating him handsomely." Karasuma replied, as if it was obvious. "But it's remarkably convenient. A creature capable of destroying the Earth that not even the military can kill...and he's willing to teach a class? Thank goodness that the only ones who know about this are the government, that principal and those E class students."
"Ouch! If I do any worse, I might end up in class E!" A voice interrupted him, making his eyes widened slightly. He looked sideways to see two students talking about grades. "Seriously?! Once you wind up there, you can kiss all hopes goodbye! They'll stick you in that satellite campus with no meals, filthy toilets, and you'll be treated like dirt by both students and teachers alike! You need crazy-good grades to have any chance of making it back!" They shared malicious gazes. "It sure is the End class! I'd rather die than wind up there!" "I know, right? Better buckle down so we won't be like those losers."
————Kunudon's special lesson————
- Teach us, Kunudon!
- I'm Kunudon, the mascot of this institution! In this segment, I'll teach you all about Kunugigaoka Academy!

*insert illustrating blocks of Kunugigaoka Junior High main campus and old campus*
- Kunugigaoka Academy's students place on average 1.6 standards deviations above the mean. It's a school filled with fun, lively friends to cheer you on! *leans over the main campus illustrating blocks*
- Really? That's super! *kids' voices*
- Everyone gets along really well, and everyone is equal! *pushes blocks of old campus and makes them fall*

- Everyone is equal! Yay! *kids' voices, again*
———back to Main Campus, Hallway———
"I see," Karasuma thought out loud, "if a handful of students are discriminated harshly against, the majority will work harder, fueled by pressure and a sense of superiority. Its structure is reasonable enough, and that satellite campus is perfect for our top-secret mission." Those End-class pariahs must be almost ready to snap, though. Those were his thoughts as he walked on the mountain of the old campus.
"Ah!" exclaimed Kaede as she saw Karasuma walking towards the classroom. "Hey there, Karasuma-san!" She stopped her running, but her legs were still going up and down, like she was in a hurry. She was holding some bamboo sticks with rubber knives tied to the top. "Hello." Karasuma greeted her, then went straight to the problem. "Starting tomorrow, I'll be helping you out as a teacher." "Oh, will you?" The grenette stated cheerfully. "I look forward to it." Karasuma replied. "So from now on you'll be Karasuma-sensei!" Kaede exclaimed as her eyes closed and she grinned widely in excitement and joy.
The Ministry of Defense staff looked around. "By the way, where is he?" Kaede answered him as Okajima ran out from class, carrying a rope, "well, Koro-sensei ruined the class's flowerbed, so to make up for it..." she showed him as they both walked to the backyard, where students are shooting and poking at the octopus teacher, who was tied to a tree branch but having green stripes all over his head as he dodged them all. "...he's handicapped himself for an assassination competition."
"A little something extra by way of apology!" Somehow Koro-sensei's voice was heard between gunshots and missed BBs colliding with the tree trunk. "You won't get many opportunities to have my movements restricted this much!"
The girl walked to Nagisa as he was not shooting the overconfident teacher. "Any luck, Nagisa?" The one mentioned deadpanned as he held his gun close. "Uh... he's definitely not taking us seriously." Karasuma appeared from behind them. "You call this assassination?"
Suddenly Nagisa snapped out of his deadpanned mode. "Hang on, going by Koro-sensei's weak points,..." he took out his note.
"Nurufufufufu! I'm afraid it's no use, Class E!" The tied but overconfident teacher laughed his signature laughter. "Even with this handicap, I'm faster than any of you! Killing me is still a distant dream—" Suddenly, the branch snapped from having bore too much sudden movements and swings.
The teacher laid silently on the ground and the students were still in their stances of pointing their weapons upward. They stayed like that for a moment. Koro-sensei's face was green by now (not literally), buckles of sweat adorned on his face -because he was laying on the ground, handicapped all in the middle of the circle that consists only of students wanting to kill him-, and the students sweat dropped.
"Now!! Kill him!!!" The class screamed like some prehistoric people hunting in groups while gripping their make-up spears and knives. Yep, totally like a prehistoric tribesmen group.
"Yaaa!!! Shimata!!! (oh hell!)" Koro-sensei also screamed as he tried to roll to avoid the "tribesmen group". "Yikes! Watch out! You could put an eye out with those things!" He yelled in fear and panic as he rolled over and over to dodge.
Koro-sensei's weak point #1: when he shows off, things get shaky.
"Those notes might come in handy after all." Kaede states as she, Nagisa, and Karasuma watched the chaotic scene laid out in front of them. "Yeah, I'm gonna keep taking them." Nagisa said as he raised his pen.
"Hey! Wait! M-My tentacles are tangled up in the ropes!" Koro-sensei desperately called as he dodged and dodged the knives and bullets that flew pass.
Koro-sensei's weak point #2: loses his composure rather easily.
"Why you little—" he said and made his jump to the roof, discarding the rope. "Damn, he got away!" The students below sweared, they had just gotten so close!
He saw them, flipped, and made himself a comfortable stand on the roof. He then raised his tentacles in victory. "You'll never made it all the way up here! You lack the fundamental capability! Take that, you stupidheads! Ahahahahaaha!!!" He crossed his tentacles pridefully and bent backwards as he laughed maniacally.
"And we were so close!" Kimura Masayoshi, a green spike head, looked furiously at the teacher who was on the roof laughing his head off.
  When he seemed to have found back his sanity, he bent forward and panted. He wiped the sweats on his face with a tentacle hand and looked up. "I'm doubling tonight's homework."
The class gasped. "So petty!!!"
Koro-sensei's weak point #3: Small minded.
"Nurufufufufu!" He laughed as he flew away with his max speed.
"He's gone!" The students below exclaimed. "But this is the closest we've ever gotten!" Meg cheered them up. "If we keep this up, we would definitely get our chance to kill him!" Isogai joined Meg to cheer the class up.
Class E started to think of the reward as they cheered. "Ya! And then we get ten billion yen!" Yada exclaimed as she got carried away and started daydreaming. "What should I spend it on?"
While they were jumping and cheering, Karasuma looked at them from the side. Junior High students talking happily about assassination? This sure is a strange place.
"Think we can pull it off, Nagisa?" Kaede asked her friend, who was jotting down notes. "Yeah," Nagisa replied with determination. "How can we live with him unless we can kill him?"
It's so strange...Karasuma thought to himself, how the liveliest students at this school are here in class E, with their target teaching them.
The scene changed, and Koro-sensei gave out his signature laugh above the sea as he soared to the sky. "Nurufufufufufu!"
—Ministry of Defense, Guest Room—
  "Those are the circumstances. Considering the Earth's current crisis, you must speak of them to no one. If this gets out, you will be forced to undergo a memory-wiping operation." A woman said.
"I'm shaking in my boots." A young low voice echoed in the room.
"All the members of class E have received the same explanation. Consider them part of the mission." The woman announced as the young teen dropped his arm to his knee. "Once your suspension is over, you will return to E class. At such, you will receive the same assassination assignment."
"So, uhhh..." the teen threw the profile he was holding to the side as he raised the green rubber knife that he was holding on the other hand all along. He bent the knife easily, being made out of rubber it is. "Will this rubber knife really work?"
"Yes. It's harmless to humans, but we guarantee it will work on him." The woman answered.
"Not bad. I don't care much if he isn't a human." The teen said as he stab the paper profile with his knife. "I've always wanted to try..." he lifted the knife, along with it was the paper profile, and dropped it to the ground. "Killing a teacher." His golden eyes glimmer with malice.
—————Somewhere—————
[Computer]

[Data D:]

[Experiment file]

<This file has password. Do you wish to proceed?>

[No] [Yes]

<Please enter the password>
•••••••••••••••••••

<Opening...>

[Subject R1-WBUD2]
[Subject S3-WBUD2]

<Opening, please wait...>

<Processing...>

[Subject profile]
[Genes and subgenes]
[Injected medicines and test results]

<Opening...>

[Y/N L/N]

"Bingo."
———————(^_^)——————-
Word count: 5650
Sorry for the song update!
Finished on 31th August, 2020