A/N: I'm so unsure if this crossover would work, but you know what F it! That's what I always say. Let's do this!

Y/N, Melascula, and Jamal were teleported somewhere.

3rd person POV

Y/N: Huh? Looks around him and sees that he's in a city. Where am I? Jamal! Melascula! Where are you!

Civilian#1: Ahhhh!!!! A monster!

Civilian#2: Another one Crap!!!!

Civilian#3: Someone call the heroes!!!

Y/N: Monster?

A man wearing a tank top with tiger stripes appears.

Tank top tiger: Stop right there monster! If you want to hurt these people you'll have to go through me!

Y/N: Huh?

Civilian#4: It's Tank top tiger!

Civilian#5: Kill that monster Tank top tiger!

Civilian#6: Yeah you got this!

Y/N: Are they talking about me?

Order: It would seem so you do have a monster like body.

Y/N: Oh right. Look man I'm not a monster.

Tank top tiger: Not a monster? Yeah right you are such a terrible liar.

Y/N: I'm telling you the truth!

Tank top tiger: You can lie your way out of this monster! I'm not gonna let you go scott free after attempting to hurt these civilians!

Y/N: I'm not here it hurt anybody! I don't even know where I am! I need to go to Seattle do you know where that city is from here?

Tank top tiger: Seattle? Never heard of it.

Y/N: What?! What do you mean?! That city is being overrun by demons right now!

Tank top tiger: Last I checked I've never heard of a city being overrun by demon level monsters.

Y/N: Demon level?

Order: Wait Y/N check that device on you.

Y/N: Yeah what for?

Order: What's the condition for it?

Y/N: It seems broken.

Order: Mhhhh I think we're not at Seattle anymore.

Y/N: No shit

Order: No I mean I don't think we're at our world anymore.

Y/N: Do you think that device just send us to another world? A different dimension of sorts?!

Order: Possibly yes

Tank top tiger: Hey what are mumbling about there?!

Y/N: Oh right nearly forgot about this guy. Look I'm not from here!

Tank top tiger: Yeah I've noticed monster.

Y/N: No!! I meant that I'm from a different universe where monsters and humans co exist with one another.

Tank top tiger: What now?

Y/N: shows him the device. This thing sent me to this world of yours! Along with some of my friends! We're at a war right now at our word and we need to go back and help our friends win this war!

Tank top tiger: What war exactly?

Y/N: A war against demons! When I say demons I really mean demons from hell not demon level monsters as you put it.

Tank top tiger: Why should I believe you?

Y/N: I don't expect you to, but I'm telling you the truth. Please help me find my friends and some people that could help fix this device.

Tank top tiger: I-...

Tank top black hole: Little bro! Need some help?

Tank top tiger: Big bro!

Y/N: Great.

Tank top black hole: Don't worry everyone! We'll take this monster down!

Civilian#7: Yeah!

Civilian#8: You got this!

Order: Guess we have no choice,but to fight.

Y/N: You sure that's wise cause they both look pretty weak.

Order: In which they are the one with the tiger stripes has about 200 while the other one with the black shirt is 250.

Y/N: Yeah I'm just gonna go and find my friends.

Tank top black hole: Where do you think you're going!? Charging at Y/N Black hole capture!

Y/N: grabs Tank top black hole's hand and tighten his grip.

Tank top black hole: Owowowowowowow!!!! My hand!

Y/N: Seriously? Let's go of his hand.

Tank top tiger: Big bro!! Charges at Y/N Tiger-like rush attack!

Y/N: with his tail he parried his attack making lose balance.

Tank top tiger (in mind): Crap I'm done for! Y/N doesn't attack. Huh? Why didn't he attack?

Y/N: grows wings. I'm leaving. Flies away.

Y/N: Where the hell are we?

Civilian: Help a monster!

Y/N: Huh? Y/N sees a demon level monster causing havoc. We'll time to step in. Lands

Demon level monster: Who are you?

Y/N: I'm the guy that's gonna stop you from hurting these civilians.

Demon level monster: Why would you help the humans? You're a monster like us!

Y/N: I'm no monster! I'm a human whether if you see it or not! I won't let you hurt any of my kind anymore!

Demon level monster: You are a disgrace of all monsters! For this you will die!!!

Y/N: the monster moves in to punch Y/N. But Y/N dodged in time and attacked. Shotgun! He hit the monster in the face blowing up the upper part of his body away leaving only the legs. That's done. No dead civilians too that's good. Well time to continue the search. Flies away.

Y/N: Where is everyone? Notices Melascula flying in the air in front of him. Melascula!

Melascula: Hmm? Y/N! They hugged each other happily knowing that they're together again. Glad to see you again.

Y/N: Me too. Have you seen Jamal anywhere?

Melascula: No I haven't.

Y/N: Then we have to keep searching.

Jamal's POV

You (in mind): What the heck happen? I was over at the Foundation checking that device that Y/N had. Then I was sent here in a city. Hmmm.

An explosion happens near by

You: What was that? Went to investigate the explosion. You came to see some people in a black and white suit lying in the ground injured.

Hellish Blizzard guard: Please... help lady Blizzard....

You: Lady Blizzard?

Hellish Blizzard: Back off! *boom*

You went to investigate the explosion. You see a guy with blades attached to both hands fighting a woman.

Royal Ripper: So this is the famous Hellish Blizzard. Must say I'm dissatisfied by your abilities your younger sister however is much better at you than this.

Hellish Blizzard: Damn you!

You: As soon as Royal Ripper went in for a stab You used your esper powers to stop him. You then twist his arms backwards a lot then throws him to the side. Are you the Hellish Blizzard that needs help?

Hellish Blizzard: Who are you?

You: I was just in the neighborhood till I hear an explosion happening here. Who was that guy?

Hellish Blizzard: Are you blind that is not a man. That's a monster.

Royal Ripper: getting back up and fixing his arm like it was nothing. Another hero? You don't look like a Blizzard member.

You: Well that's because-

Hellish Blizzard: He's my secret weapon!!!

You: Seriously?

Royal Ripper: Alright let's see how powerful this weapon of yours is then. With speed he reaches Jamal and begins slashing him with his blades.

You: thanks to your force field you remain un damaged. You then push Royal Riper back. Hell Cutter! With the rubble around you. You picked them up sharpening it and enhance it with your esper energy then throw it at Royal Ripper.

Royal Ripper: Gah!!!!! On his knee spitting blood. Dammit!

You: Is every fight I'm in gonna be easy? Then he pushes Royal Ripper out of the building. There you go. Stares at Hellish Blizzard Also what's with that secret weapon comment?

Hellish Blizzard: Who are you? Are you with the association?

You: What association? I was teleported to this city just a few minutes ago.

Hellish Blizzard: Teleported?

You: Yeah I was with my friends earlier then later on I was teleported along with my friends and I'm trying to look for them.

Hellish Blizzard (in mind): Maybe I could use this to my advantage.

Hellish Blizzard: Why don't you join me?

You: Join you?

Hellish Blizzard: Yes join me and I'll fill you in on what's going on in this city. I'll even help look for your friends.

You: Ok sure

Hellish Blizzard: Now tell me how do your friends look like?

You: There's Melascula she's kinda like a esper, but she uses darkness. She has pink hair,wears pink stockings, and has a pink bow on her white suit. Then there's Y/N he looks like an ink Demon. Has no eyes, has a big smile on his face, wears a black and white suit kinda like the suit of the guys I saw at the entrance.

Hellish Blizzard (in mind): A suit just like my men? Never heard of a guy with a big smile on his face and no eyes. Is this man I recruited even human?

Hellish Blizzard: Tell me more of this Y/N.

Back with Y/N and Melascula.

3rd person POV

Melascula: Y/N? Where are you?

Y/N: Over here. Did you find a hoodie or something to cover me?

Melascula: Yes here.

Y/N: Puts on the disguise.

Y/N: Thanks Melascula.

Melascula: Can't believe they attacked you on sight like that.

Y/N: Yeah whatever this world is. It seems like humans and monsters are at war with one another.

Melascula: Can't believe we're in another world. Do you think if you summon Reap it'll come to you?

Y/N: Never tried let's see. Reap come to me!

Back at the Foundation

Susie: Galand, Jim what are you doing?

Galand: We're waiting.

Susie: Waiting for what?

Galand: For Reap to go to Y/N. You see Jim had an idea which if Y/N were to call Reap. Reap will go to him, so we'll hold on to Reap and see where Y/N, Jamal, and Melascula has gone to.

Ralsei: Do.. do you think it'll work?

Galand: We got to try something. Who knows where those three has gone to.

Reap hears Y/N's call and starts floating up

Galand: There now Jim hold on to it!

Jim and Galand holds on to Reap with all their might. Reap stops moving in the air.

Galand: Huh? Whoa-

Galand and Jim disappeared in front of Susie,Ralsei, and Kris.

Ralsei: Oh no.

Susie: *sigh* I'll tell the others what happened.

Galand and Jim got teleported to the world that Y/N, Melascula, and Jamal were in.

Galand: Hoooollllddd ooonnnn!!!!! Losing his grip he fell to the floor landing in the forest. Ow!

Jim lands on top of Galand.

Galand: Get off me! Flies up. There! Y/N is in that city! Lands on the ground. Well Jim time to go.

Gouketsu: Where do you think you're going?

Galand (in mind): This presence.... what is this?... 4,700,000?!.... turns around to see Gouketsu

Galand: We were just about to head to the city.

Gouketsu: Have you forgotten that we have a meeting at the association?

Galand: Meeting?

Gouketsu: Oh so you two haven't heard of the Monster Association then?

Galand: No we haven't.

Gouketsu: Well then come and join us at the Monster Association meeting at City Z.

Galand: looks at Jim. We may not have a choice here. They followed Gouketsu to the Monster Association.

Back with Y/N and Melascula.

Y/N: Reap reaches Y/N and he grabs it. Looks like it does go through different worlds. Good to know.

Melascula: You don't know how to use it to get back do you?

Y/N: No, but I do know we got to get this teleporter fixed.

A limousine appears across the street.

Civilian: Look it's the Blizzard Bunch!

Y/N: Who are they?

Jamal comes out of the Limousine.

Y/N: Wait Jamal?! Hey!! Jamal over here!!!! Waving at him.

Jamal: Y/N!? Goes over to Y/N and Melascula. Where were you guys? Y/N why are you wearing that hoodie?

Y/N: Look just don't take it off people here will immediately call some monster hunters to kill me.

Jamal: What for?

Melascula: We were transported to a different world. A world where monsters and humans are at war with one another. Since Y/N doesn't look human like us the monster hunters "heroes" as people call them will come over and try to kill Y/N.

Jamal: Oh.

Y/N: What's with the suit?

Jamal: Oh I saved some hero and she said she would help me look for you guys if I join her.

Y/N: Well guess you won't be needing her anymore then.

Hellish Blizzard: Hey newbie!! Get over here!

Jamal: Yeah I'm just gonna join you guys instead. Turns to Hellish Blizzard. Sorry, but I've already found my friends so this is where we part ways! Bye!

They leave the area.

Hellish Blizzard: What?! *snaps* Wild Monkey! Eyelashes!

Wild Monkey/Eyelashes: Yes miss Blizzard!

Hellish Blizzard: I want you two to keep your eyes on him and his friends there. Make sure no one notices.

Wild Monkey: On it!

Eyelashes: We'll get it done!

Hellish Blizzard (in mind): He thinks he can just leave me like that then he got another thing coming!

Y/N: So did you learn something new about this world here? Or was it just us?

Jamal: Actually I learned that there's a Hero Association. In the Association there are many kinds of heroes. Weakest to strongest. C to B to A to S classes of heroes. Not only that whenever there's a monster attack the association sends their heroes to fight those monsters. Speaking of monsters they even ranked the monsters too. Weakest to strongest.
Jamal: Wolf - Any potential threat that poses a danger to an unknown degree.
Tiger - Any threat to a large number of people.
Demon - Any threat to a city and its people.
Dragon - Any threat to multiple cities.
God - A threat endangering the survival of humanity in general.

Y/N: Wow

Jamal: I even learned that there's a smart S class hero that could help fix that device.

Melascula: Really?

Jamal: Yeah if I remember correctly his name was "Child Emperor".

Y/N: What kind of name is that?

Jamal: Beats me which is why I'm gonna join the Hero Association. Melascula could join in too.

Melascula: I don't know.

Y/N: What about me what should I do?

Jamal: You will be joining the Monster Association.

Y/N: Say what now?

Jamal: No like you'll be our spy. Ya know?

Melascula: Then I'll join the Monster Association too.

Jamal: Bad idea.

Y/N: Yeah won't the monsters immediately try to kill you?

Jamal: Which is why she can't go there she's looks like a human esper with darkness powers.

Melascula: But!...

Y/N: I'll be fine don't worry. Jamal do you know where the Monster Association is at?

Jamal: I don't know it's exact location, but it was rumored to be at City Z.

Y/N: City Z got it! Grows wings. Meet you guys later. Flies away.

Jamal: Well let's go Melascula.

Melascula: To where?

Jamal: The Hero Association of course. We're gonna join them.

Hellish Blizzard: Hold it right there!

Melascula: Who is she?

Jamal: Hellish Blizzard she's a B class rank 1 hero.

Hellish Blizzard: Where do think your going?

Jamal: To the Hero Association. We're gonna register and join in on ten monster hunting.

Hellish Blizzard: Tch you got a lot of nerve for leaving the Blizzards group like that. *snap* some Blizzard group goons shows up.

Jamal: What's this Blizzard?

Hellish Blizzard: I'll forgive you if you join me again. If you do then you and your friend there won't be harmed.

Jamal: No that's not gonna happen.

Melascula: Aren't you supposed to be a hero? What kind of hero just has a gang and attack someone like this?

Hellish Blizzard: You don't get it do you? You need to join a clan in order to survive in the association. There will be other heroes that will put you down just for out ranking them.

Y/N: Well that's just stupid and pointless. Appears behind Hellish Blizzard.

Hellish Blizzard: Who are you?

Y/N: I'm one of Jamal's friends. Also that whole putting each other down just because of ranks. Now that's just pathetic. You don't become a hero just for the fame and fortune you become a hero because you got lives to save and protect. The hell does ranking serve just more money and crap. Fuck that! You're just wasting your time.

Order: Mhhhh by the looks of her power level and compare to her goons she is much stronger and should've been in the higher ranks.

Y/N: What's more sad and pathetic is that you decide to stay in B class when you could just move up to A like nothing.

Hellish Blizzard: Shut your damn mouth! Hell Crush! She used the ground beneath Y/N to raise two walls between him and crushes him.

Y/N: breaks free un damaged. Yeah you're the one that's not gonna survive. Right Jamal?

Hellish Blizzard: What? Jamal has all of her goons down on the floor with his esper powers. Hellish Blizzard then grabs a knife and stabs Y/N in the neck. Ragh!

Y/N: Ok that stings. Pulls the knife out.

Hellish Blizzard: What?! What are you?

Y/N: Taking off his disguise I'm Y/N also was known as the "Ink Demon" back in hell.

Hellish Blizzard: A monster! Wait that grin! No eyes! And a suit! Jamal you're with the monsters?!

Jamal: Calm down and no I'm not with the monsters. Y/N just got in a terrible incident with a horrible human man. That man turned Y/N into this.

Y/N: Yeah it kinda sucks, but hey at least I'm half demon.

Jamal: You don't have to worry he won't attack. He isn't evil he just wants to help and save lives.

Hellish Blizzard: What?!

Melascula: It's confusing at first, but you'll learn soon enough. For as you see we're not from this world.

They explain to Hellish Blizzard about their situation and their plan with the associations.

Hellish Blizzard: I see. This... is a lot to process.

Melascula: You do understand the plan yes?

Hellish Blizzard: Of course. I still can't believe that you have a mon-

Y/N: Could you not with that?!

Melascula: He hates being called that.

Hellish Blizzard: Right sorry.

Jamal: Anyway Melascula and I will just be heading to the Hero Association and Y/N will be joining the Monster Association. Bye

All three of them left leaving the confused Hellish Blizzard.

Back at the Foundation.

Director Jones: So we don't know where those 5 have gone off to. Better yet 2 of those men that are missing are our best ones?

Susie: Yeah

Director Jones: flipping over a table. Well Goddammit! Well it doesn't matter you said that you have someone else that is as strong as them at the Underground?

Undyne: Yes that would be Asriel.

Director Jones: Well time to head to Seattle. Asides we can't just stay here the 9 Commandments have 079 on their side and since they have that AI it'll just shut down all of our power and turn our machines against us.

105 (Iris): Oh I always wondered why that computer was dangerous.

Director Jones: Alright people get on those trucks because we're heading to the mountain at Seattle to rescue the survivors and create a plan to take back that city!

Everyone starts getting on the trucks and are on their way to the mountain.

A/N: Well I hope I did this right. Still unsure how to power level the characters on One Punch Man. Anyway I hope y'all enjoy and see you in the next chapter.