With a loud series of crashes, explosions and screams, Manual received a call, "What did you say!? Vilains appeared!? Don't worry! I can head there right now!" He turned to Naoki and Tenya. "You two, stay with me, we're running!" They took off, Naoki tapping Ricochet's button, double clicking Blood Tempter's, and, in doing so, preparing for the worst by activating his best offensive Quirk, and best healing Quirk.

Within seconds of this, Naoki saw Tenya stop, taking off in a different direction. Naoki stalled, unsure if he should, because, he had also felt something when activating Blood Tempter. Kurogiri was nearby as well, and, beings as Stain's MO wasn't flashy, yet, Kurogiri and that Shigaraki creep were, Naoki was stuck on what he could, and should do. Pulling out his phone, he shot Naomasa a message. The warpgate guy is near Hosu. Blood Tempter sensed him. I'll be able to find a hideout now, unlike before... Guess he doesn't clean his gates well~

The next message was to Manual, who he had exchanged numbers with before, letting the Pro know where they'd separated, and, letting him know his plan, in short, along with a possible location they'd end up, that he'd try and lead things to.

With a worried sigh, he tried calling Dabi, and, grew unimaginably concerned when the number went straight to voicemail. After two more tries, he settled for a message, a simple apology for his ensuing stupidity, and ensured recklessness.

After hitting send, he took a deep breath, and ran after Tenya, activating a vector to conceal his presence. While running, he focused on the two USJ Villains, and their conversation, committing it to memory to relay to necessary people later on.

When he arrived, Shouto and Izuku were there, as well as another injured Pro. Shouto had just taken two blades into his blazing left arm, while Stain then went after the other Pro. Naoki seized this small chance. He slit his fingers, dripping a bit of blood into Native's wounds, holding a hand over the Pro's mouth to avoid drawing attention right to him as Izuku jumped to intercept the Hero Killer.

"Midoriya!" Shouto shouted as the green was repelled from Stain, just as Stain was redirected back toward the ground. Seeing this, Shouto muttered, "Naoki?"

Izuku had noticed Native move, subtly, seeing the tell-tale signs of Blood Tempter being in use on him, meaning Naoki was near. "Naoki! Why-" Izuku yelled, seeing Naoki now land in front of him, between the green and the Villain.

"You can't! Izu! Shou! We're not even heroes! We don't have licenses! This isn't like the USJ! With me here, there's no need to harm him, and there's no reason to kill him! Native's going to be healed soon, Tenya's going to be fine! Just stay back and keep those two out of this! Please, let me handle this! Harming people, taking lives, it's not the only answer! Now get back!" Naoki yelled, his eyes catching Izuku's attention, showing his emotions as they always did.

"I don't know who you are, boy, but if you intend to get involved, I'll kill you too." Stain muttered, a chipped blade pointed at Naoki as the raven blocked him from his prey, and, added yet another distraction to the day.

Naoki turned to him, "That earlier punch, you've got to be injured. Please don't drag this out. Let them go, and test me instead. I was adopted by All Might, so that means, only you are qualified to test me!"

"What!? You... I see... I recognise you now. Very well, but, once I'm finished with you, they're next!" Stain yelled, a look of fascination in his eyes as he charged. He threw a knife, distracting Naoki. While he dodged it, Stain drew in close enough, sticking his blade through Naoki's arm, pulling it back out. "You're weaker than those three, slower, and you consider yourself All Might's son! Ha! Don't make me laugh. I'll cull you from this world too!"

Naoki drew his own blade, the edges dulled, aside from a now three inch span of the blade near the hilt. "See how that works." Naoki replied as Stain lifted the blade, licking Naoki's blood clean off.

With no reaction aside from a flinch, Stain was stunned. "What? How!?" He asked, seeing his Quirk ineffective against the child, the blood he'd ingested leaving an odd taste behind, so different from anything, any blood he'd ever ingested.

"I also use a Blood Quirk, Stain. By you ingesting my blood, just now, I am going to learn a lot about you, and, your Quirk isn't able to work on me, because... I don't have a blood-type as every other human does. My 'type', if anything, can either be called 'C', for Curer, or, 'H', for Horror. I assume your Quirk wouldn't take that into consideration. With my own blood, I can cure someone or, destroy them from the inside. Want to guess which you just ingested, Hero Killer?" Naoki explained, baring his own blade.

"You... You used the 'H', to kill me, isn't that right?" Stain asked, still close to Naoki, eying his movements, his breathing, everything, to read the boy in front of him.

"No. I was right. You are injured... Your pretty beat up... Let's take care of that..." Naoki muttered, activating Blood Tempter.

"W-What... What's... Happening?!" Stain asked, the unfamiliar feelings from Naoki's Quirk running through him.

"Broken ribs, fractured facial bones, skull, jaw, and cracked teeth... All of those were just repaired. Now, we're on more level grounds. I can heal any damage I make to you now. So, are you still up for a fight?" Naoki asked.

"You healed me... I'm going to kill your friends, and every false hero before me, yet, you just healed me. Why?" Stain asked.

"Because you were hurt. I may be just a kid with no past, no family, few friends, and even fewer years or memories in my life, but, I know my morals. I will stand by them. And, whether you're a hero, a Villain, a citizen, a blinded snake with no possibility of survival, a kitten left in the rain after being hit by a car, a dog injured while protecting young... All of those are still alive. Still living beings. You are, too. So, leaving one injured, who is right before me, and I am able to help, is wrong. I want to be the kind of hero who saves lives, not just those of heroes, or Villains, not just humans either. You were injured, and I couldn't ignore that. So, now that you aren't, I'm free to properly restrain you until help arrives from people who can arrest you."

"You think it'll be that easy? Think again!" Stain yelled, swinging his blade down, having to dodge the flames shot at him as Todoroki made to back him up.

"Naoki! Why did you just stand there?" Shouto asked, Naoki turning and grinning.

"Shou-san, I've got vectors up. He wouldn't have struck me. Please remain out of this and contact Pros and the police. Also, help get them out of here. I'll restrain him until then... And, don't get involved either. I keep warning you about bodily damage from the Quirk you use, and it applies to others as well. You could burn someone, or give them frostbite too. Keep that in mind."

"You seemed to forget about your opponent, rookie." Stain shouted, drawing a second knife, throwing it to hit Shouto, only for Naoki to catch the blade between two fingers.

"And you ignored me just now as well. Thank you for the knife, but, here, have it back." Naoki tossed it safely and professionally back, the Hero Killer stunned again, but, caught it, sealing his fate. "Thank you kindly~" Naoki finished, using Ricochet, combined with Blood Tempter, to restrain the Hero Killer, safely and with no possibility of harming him. "Let's head to the street, Stain, sir... Best to get you out into the open before you're able to slip away... That Warp gate guy is still closeby... I can feel it..."

"You... You know them? How?" Stain asked.

"They attacked my classmates at school, but, that's not what you're meaning... This same Blood Quirk, I used it and have been monitoring their movements around Japan since. After tonight, there's more a chance I'll be able to find their hideout." Naoki answered, walking, and, causing the restrained Hero Killer to follow, surprised, but, not irrational, violent or eager to kill the raven. "Stain, this Quirk will ensure you aren't harmed, so long as you don't try to harm yourself, and, I can make sure you aren't harmed by the others here either. Izu, Tenya-san... Here, Shou-san, give it to them." Naoki offered his hand to Shouto, the bi-coloured taking the offered crimson drops.

"Are you sure you won't-" Shouto began.

"Please, just get that to them. I can't ensure Tenya-san won't have permanent damage, but, I'll still heal what I can... Izu should be fine, and Native will recover nicely..." He stopped Shouto from walking away, grabbing the injured arm, gently taking out the knives and healing the wounds with the solid stream of blood still coming from his arm. "There. You'll be fine, too. This will make up for all the blood you lost, but you should still get proper treatment for exsanguination... You lost more than is safe..." He turned to Tenya. "Tenya, I spent last night researching spinal injuries, everything I could... I may have a way to restore Tensei-san's legs... It has a risk of not working, and, it's about 37%, but, the rest of that, is a chance he'll recover. Complete, instantaneous recovery, though, is only 15%. Everything between there is recovery, but, he'll need physical therapy and a few weeks of re-learning how to fine-tune his control again. I was trying to tell you that I may be able to help him the other day, but you assumed I was just offering words of condolence or apologies. If I'd known you were going to do this, I'd have been more aggressive when trying to tell you... I'm sorry..." Naoki pulled his phone out, having felt the call incoming. With a sigh, he answered, his mood immediately changing, back to the personality they were used to him showing in class. "Hello? Yes... Yes, sir... I know, I apologise. Uh..." He paused, looking at the street they'd just exited. "4-2-10 Ekou Street... Yes, I understand. We have... Yes. Understood." Naoki hung up, sighing again. Overwhelmed, his shoulders slumped, a frustrated groan as he faced the rest of the group, the Hero Killer still eying him, seeing his eyes, the one that had been ice blue just before the call, now lavender, the other still blood red. "Izu, Shou-san, they'll be here in just a few minutes... Endeavor sent Ji-ji-san, and he's... Um... Not happy..." He turned to Stain. "Stain, I am sorry about this, but you'll be taken into custody. I apologise if I failed your test."

There was no response, but, the Villain's eyes narrowed, and he relaxed before closing them for a short few minutes, until the Pros arrived. While waiting, Shouto, Tenya and Izuku took all of Stain's weapons from his reach, the Hero Killer less than pleased, but, not putting up a visible struggle to fight back.

Gran Torino was among the first, stragglers following closely, shocked when they saw the Hero Killer, seemingly willingly standing idly by.

"Naoki, you will need to explain what happened. Your messages to Tsukauchi and Manual were, well, normal for you... But, how this came about... I can imagine you followed the same morals you had the last time I saw you, asking me for help with that serpent. You did good by following the law. As for the rest of you, there's more to be said, later, though." Gran Torino lectured.

"How is he doing that? The Hero Killer's just standing there..." One asked. Another lower-powered Hero made a snide remark, jumping when he arrived, to attack, Naoki blocking, setting the man down and pulling his own card and lectured the Hero.

"What are you! Blind? He's restrained, and not going to harm anyone! There's Heroes all over here, and you could tell they weren't hostile, or attacking, yet, by some herculean leap in logic, you assumed you'd just seize the chance to make a name for yourself, taking him down? Really... Not cool, man... Is common sense or basic human decency dead to you or something..." Naoki lectured, the man kneeled down and apologising. "Don't apologise to me! I'm not the one you were going to attack unnecessarily!" Naoki responded, pointing to Stain, making the Hero scowl at the implication and, leave the immediate area to avoid Naoki making him.

"Hey, kid." Stain spoke, drawing the attention of almost everyone there. "Why are you still keeping people from attacking me? You could have let him and there'd have been nothing illegal about it." Stain asked.

"Eh... You're already restrained, and there's no reason to attack someone who can't even defend themselves... Even heroes shouldn't be allowed to... We are students, so it's understandable why we shouldn't... But, you aren't harming anyone, right now, you aren't a threat, so letting him do that when I'm restraining you... It's my responsibility to defend you until you're taken in to custody, since I am keeping you from being able to do it on your own..." Naoki answered, a few members of the crowd wondering why Naoki replied at all, leading Naoki to entertain himself on that, "Let me guess. You assumed it was to do with me not wanting to have to heal you again? Save my Quirk and energy... Something like that?" Naoki returned his own question.

"Something like that, perhaps." Stain replied.

"I'm not really worried about that. My Quirk isn't just for me, I want to use it to protect lives, like I said, not just heroes, Villains, citizens, or even just humans... Any life I can. Yours is no different... I've got pretty good stamina with this Quirk, so I'm not concerned with preserving its energy for myself. If I failed to keep someone from harming you in this situation, I'd still heal you, even if it ran me out of energy." Naoki finished, aware of the stares, yet, unconcerned. Tenya apologised, Native, SHouto and Izuku were conversing, Naoki just remaining calmly focused.

Out of nowhere, a Winged Nomu came flying, Gran Torino yelling for them all to get down, and, without time to actively control the vectors keeping Stain restrained, not to mention the strain he was feeling with everything piling up so much for him, Naoki jumped over, physically helping those vectors get Stain down to safer heights, himself and Izuku the only two still at higher reaches.

The being snatched Izuku, Naoki yelling out, but, being focused on his vectors, had a choice of saving Izuku, or, restraining Stain. The Nomu was bleeding, some landing on Naoki. Stain licked the blood, making the Nomu paralysed.

"Save that brat. He and you are worthy enough. I won't flee, I give you my word." Stain muttered.

So, Naoki did, releasing the vectors on Stain, but, keeping the Blood Tempter in place, to at lease limit him if he tried. The second he could move, though, the Hero Killer ran, surprising Naoki as he jumped up, having pulled the blade from Naoki's sheath, and stabbed the Nomu, driving it to the ground.

"The word hero has lost all meaning in this society! The world is overrun by fakes and criminals like them, with fake petty dreams! They must all be purged! You, boy-" He looked to Naoki, who was now right beside the Villain, ready to step in, but, tending to Izuku for the moment. "And you... You two are almost worthy..." He had spoken to the two of them quieter, now continuing his speech, handing Naoki's sword back by slipping it back into its sheath. "Everything that I do is to create a stronger society."

Naoki's ears picked up the unmistakable sound of Tomura's voice, near enough. "Hey. Hey! HEY! What the Hell! This is no fair! Why did he have to go and kill that Nomu!? And why are those brats here?! I'm so mad, I don't even know what to say!" Naoki looked up, following the direction of the creep's voice, his voice caught in his throat, seeing them, barely, but, they were there. "This is a mess! Why do things never go the way I want them to!"

Back in the location, Naoki's attention was redirected, the crowd of Heroes now panicking.

"That kid... Did he let the Hero Killer go?"

"Did he just save that kid?" "No, he's gonna take them both hostage, I think."

"Everyone be on your guard! We've got a fight on our hands!"

"I wasn't fleeing. You just weren't going to be fast enough, and I still had a point to prove. You can restrain me again, son of All Might, just allow me to stand." Stain admitted.

So, Naoki took the chance, returning the vectors to Stain, and allowing the Hero Killer to stand, as an unwanted voice wrang out.

"Why are you all standing around like fools!? The Villain must have flown this way, right?" The no. 2 asked, arriving on scene after his escaped prey.

"You took care of the rest?"

"Mostly. It got a little rough towards the end. Hold on... Don't tell me... That man is-"

"Endeavor..." Naoki muttered, the Hero Killer looking toward the source of the raven's gaze, which, for the first time he'd seen of the brat, hinted of fear. "Endeavor." Stain answered.

"HERO KILLER!" Endeavor yelled, preparing flames to attack.

"WAIT, Todoroki!" Gran Torino stalled Endeavor as Stain continued to speak. Naoki gestured Izuku to stay down. Stain's eye coverings slipping off, Naoki seeing scarring on the man's face, and, the area being drowned in such a powerfully overwhelming thirst for blood. Naoki was almost swayed by it, his own fear-induced hatred for the no. 2 being drawn out by the close proximity of the man who scarred his body.

"You false hero! I'll make this right. These streets must run with the blood of hippocrates. Hero! I will reclaim that word! Come on!" He was still taking steps, even with Naoki's restraints, even with the bodily and muscular-skeletal restrictions Blood Tempter was making, he still took step after step, "Try and stop me, you fakes! There is only one man I will let kill me! He is a true Hero! ALL MIGHT IS WORTHY!!" The aura he emitted was terrifying, but, with all the control he could muster, Naoki stopped him, putting every possible vector around the man, stopping his progression by force, so, as he tried to take his next step, was frontally stopped by the barrier, halting him in place as Naoki also slowed his heart down, just enough, and for just long enough to knock him out without any detriment. Once he was out, stalled in place, still standing, Naoki dropped all the rest of his Quirks, prepared to physically catch him when he fell, but, the sheer conviction of the Hero Killer left him standing, even when nothing was holding his upright anymore.

"I... Think he's... Out cold..." Endeavor muttered.

"I slowed his heartbeat enough to knock him out... Even with vectors, restraints, and Blood Tempter limiting his body so much, he still kept going... I've released them, but... He's still upright... He wouldn't have stopped until he succeeded..." Naoki announced.

"Naoki... Is he still..." Izuku began, standing himself upright.

"He's completely unharmed... Just unconscious... That last vector I tried wasn't going to work, so I had to resort to slowing his heart..." Naoki made to stand, not even able to fully straighten his knees before he tumbled back down, concerned shouts unheard as he slipped unconscious.