Chapter Text
One minute Katsuki was telling his Yamikumo how much of an angry little gremlin he looked like at the moment and the next, he was being pushed through some sort of portal.
Arriving on the other side of the portal, Katsuki lost his balanced and fell on the ground of wherever he was now.
“Ouch,” He groaned, and opened his eyes, (he didn’t realize he had closed them) only to find a class...that looked extremely similar to his, staring at him. “Dude, he looks just like Bakubro,” one of them seemed to say a little too loudly, only to be elbowed by the boy next to them.
Looking around the group of people, two caught his attention, the first one being someone who looked exactly like his Yamikumo but with green hair and eyes. The boy was just....gawking at him, and Katsuki stared back, very confused. Looking more to the right, Katsuki was met with the second person he locked eyes with, which was the one in front of the green-haired boy, the one who.....looked exactly like him.
This was getting kind of creepy and the complete silence in the room was making him uncomfortable so he decided to do what he did best, start conversation.
“Um...Hi-“ Katsuki tried to say but yelped as he was interrupted by a scarf tightly tying itself around him. Turning to see who it belonged to, he squeaked. A tall man with black hair, wearing all dark colors, was straight up glaring at him, eyes glowing red, as if Katsuki had killed his puppy or something. “Who are you and what are you doing here.” the man asked sternly and Katsuki opened his mouth to answer but then quickly decided against it. He didn’t know where he was or who these people around him were, even though they looked awfully similar. He couldn’t just tell them stuff and risk putting himself or his Yamikumo in danger-
Yamikumo.
Katsuki’s eyes sharpened as he looked across the room again. No sign of the purple-haired boy anywhere.
At this realization, he stared at the ground, hair falling to cover his eyes, a familiar dulling feeling slowly overtaking his features. Where was Yamikumo? Was he safe? Did these people do anything to him? Katsuki really hoped not, he didn’t really want to kill anyone today but he wouldn’t hesitate. He could use his quirk but that would probably make more of a mess rather than his knife...yeah, if these guys hurt his Yamikumo he’d use his knife and-
“Hey, I’m talking to you.”
A voice took Katsuki out of his darkening thoughts and he looked up, once again meeting the eyes of the taller man. His eyes weren’t glowing anymore but he continued to glare, his scarves around Katsuki not faltering in the slightest. Katsuki stared at the man and ultimately made a decision, he’d tell them what they wanted to know and ask for info in return. After all, if they threatened him there was always Plan B.
“My name is Bakugou Katsuki and for what I’m doing here...I’m not sure.” Katsuki gave a small smile but the man continued to glare, the silence in the room once again stretching out. Katsuki decided to take this time to ask his questions, “Hey so, who are you guys and where am I...?”
The man looked as if he was deciding on his answer until a familiar voice started screeching.
“AHHHHHHHHHH”
Another portal had opened from above and everyone’s attention was brought to the noise as a familiar gangly-limbed boy fell from the ceiling next to the desk of a girl who looked extremely similar to Yuu. Katsuki’s eyes widened and he immediately started squirming, trying to break free, only to have the scarves around him restrict him from doing so. “YAMIKUMO!” he yelled as he felt his self control start slipping from him once again. He was going to kill every single one of these bastards if his Yamikumo got hurt because they wouldn’t let him protect him.
Just as Yami was about to hit the floor, the girl who looked similar Yuu touched his side and the purple-haired boy slowed to a stop. Once close enough to the ground, the girl touched the tip of her fingers together and called out “Release” then slumped back in her chair as Yami hit the ground from only a few centimeters above it.
“YAMIKUMO? YAMI, ARE YOU OKAY!?” Katsuki continued to squirm, hoping to get free to check on his best friend.
“Fuck...” The boy mumbled under his breath as he got to his feet, rubbing the back of his head. Taking in his surroundings for the first time, he stared at everyone and sighed, looking unamused, then looked at Katsuki who was staring back with a very worried expression on his face. “Katsuki,” he slowly started walking forward towards the front of the classroom where Katsuki sat, tied up, “What did you do now?”
“Hey! It’s not my fault this timeee~” Katsuki said back smiling. Now that he realized his Yamikumo was fine, Katsuki was just peachy.
“Yeah? Well I’m pretty sure people don’t tie others up for no reason.” The shorter boy replied, stopping in front of Katsuki as he positioned himself onto his knees.
“Okay, can someone explain what the ever loving fuck is going on?” An irritated-sounding voice demanded from behind them. Remembering that other people were in the room, the two boys turned to find the source of the voice and out of no where, the whole class erupted with chatter.
“Why does that dude look like Bakugou-”
“Forget that, why is he smiling-”
“SHUT UP IDIOTS-”
“Oh my god, Uraraka are you okay?”
“This is against school policy, these people are intruders-“
“Why does that one look like if Midoriya and Shinsou had a child-“
“AH! G-GUYS DON’T SAY THAT-“
“What are they doing here?”
“Are they with the league? They came through a portal-“
“OMG THE ONE THAT LOOKS LIKE BAKUGOU IS SO CUTE-“
“I SWEAR TO GOD RACCOON EYES-“
“Everyone.”
The whole class shut up and all attention was brought back to the black-haired man.
“I’ll be stepping out to get principal Nedzu, Iida is in charge until I get back. You all know what to do if something goes wrong,” The man stated and with that, let loose his scarves that were restraining Katsuki and left the room.
Once free, Katsuki stood up and hugged Yami from behind, burying his face into the smaller boy’s hair. “Yami, I missed you~” he said, his voice muffled, as Mikumo struggled to get free. “We were apart for like 5 minutes idiot,” The boy replied, ceasing his struggling as he realized there was no way he was getting free anytime soon.
The one that had been referred to as Iida started to approach the two with the rest of the class, except for the boy who looked exactly like Katsuki and one with multicolored hair and eyes, following close behind. “WELCOME TO CLASS 1-A! IF YOU HAVEN’T COME WITH THE INTENTION TO HARM US OR ANYONE ELSE, WE ARE MORE THAN HAPPY TO HAVE YOU HER-“
“Yeah ok, ever heard of an inside voice big guy?” The boy in his arms interrupted, earning a few snickers from others around them and a nervous laugh from Katsuki.
“Heh, he’s just kidding-“
“I’m not.”
“Anyways,” Katsuki started, pulling Yami closer to him, “What’s your guys’ names?” he questioned and the one who looked like Yami if he was broccoli-themed stepped forward.
“If you don’t mind, could you guys tell us yours first?” The boy asked, notebook in hand, and Katsuki smiled.
“Of course! I’m Bakugou Katsuki and this is my Yamikumo!” Katsuki said brightly.
At those words, Yami blushed bright red, “Oh my lord, I’m going to kill you. My name is not ‘Yamikumo’ and I’m not yours!” He fumed and Katsuki laughed, “Not yet~” he replied, earning him an elbow to the stomach which caused him to finally let go of the smaller boy.
Turning back to the green haired boy and the rest of the class who had been watching in amusement, Yami introduced himself. “My name is Mikumo Akatani if you must know, and let me make one thing clear. We,“ He started as he pointed between him and Katsuki, “Are not friends-“
“We’re boyfriends~“ Katsuki cut in, finally recovering from the elbow to his stomach.
If it’s even possible, Yami got even redder. “WE ARE NOT BOYFRIENDS-“
“Ever heard of an inside voice big guy.“ Iida mumbled, still kind of salty from being interrupted and the boy with the black lightning bolt in his hair, along with the boy with weird elbows, started laughing like that was the funniest thing in the world.
At this point, Yami looked like he was about to explode, but then sighed and walked outside the classroom to stand by the wall and calm down.
He peeked outside the door to make sure his Yamikumo was doing okay and once he confirmed he was, Katsuki went back to join the group. When he got back, the green-haired boy had another question for him.
“Just trying to confirm a theory here....what’s your quirk Kacch-Katsuki?” The boy stuttered. Katsuki wondered what it was that the boy was about to call him, but dismissed it and answered the question. “Well my sweat is made of nitroglycerin and I use it to make explosions! It’s actually really cool and super helpful! This one time, me and Yami were at this festival and there was this dude who was running a food stand and we had got and eaten what we had ordered but then my Yamikumo had to-“
“Katsuki! That has nothing to do with your quirk whatsoever and I’m pretty sure they don’t wanna hear about that!” The very boy he was just talking about snapped, swiftly re-entering the classroom to try to shut Katsuki up, a light blush overtaking his face once again.
The green-haired boy laughed a little, “It’s alright, I do have one more question though-“
“Izuku, we haven’t even introduced ourselves yet,” A female voice chimed in.
“Oh! I’m so sorry, I’m Midoriya Izuku and this is Uraraka-“ Midoriya said as he gestured to the girl standing next to him before he was pushed out the way by a pink girl with horns who approached Katsuki with a big smile, reaching to shake his hand. “Hi! I’m Mina and you are SO CUTE, let’s be friends!” Mina exclaimed enthusiastically before being pulled away by a spiky red head while the two boys that were laughing earlier also came to introduce themselves.
After a good amount of time spent on introductions, the desks were moved so the alleged Bakusquad plus Midoriya and Uraraka could sit with him and Yami and have some Q and A to answer a few questions and ask some of their own.
“So how did you guys get here?” Mina asked, leaning forward.
“Well I’m not exactly sure,” Katsuki started, arms around Yami who had been forced into his lap and blushing ferociously ever since, but not trying to leave. “One minute I was walking to UA and next I was falling through some kind of portal and landing here.” Katsuki answered.
“So maybe you guys are from some kind of other world? I mean, you couldn’t have been heading to this UA and it makes sense I guess since there’s probably a quirk for pretty much anything and our Kacchan is right over there so you could be some kind of doppelganger...but then what about Mikumo...” Midoriya started mumbling to himself, getting lost in thought, while Katsuki stared with a small smile, suddenly entertained.
“I just can’t wrap my head around how weird this is-“ Kaminari laughed. “I mean, we have a Bakugou too and he’s an angry Pomeranian 24/7 while you’re all sunshine and rainbows.”
“KAMI! Do you have a death wish?!?“ Kirishima slapped his arm, causing Sero and Mina to outright cackle.
“Wait, you mean that guy over there who looks exactly like me has the exact same name as well? Can I go meet him?” Katsuki asked as he started to pick up Yami from his lap, who immediately started protesting to put him down, only to have Kirishima tell him that’s not a very good idea.
“Yeah, our Bakugou has...a bit of a temper,” He said nervously. This new information caught the purple-haired boy's attention.
“You mean to tell me that there’s a version of this guy,“ He asked, pointing to Katsuki who was once again seated behind him, “who gets mad?“ He laughed sarcastically and got up, starting in the direction of the Bakugou who had been glaring at the group from afar, but unusually calmly. “I gotta see this.”
“I really wouldn’t do that if I were you-” Sero warned, but his comment went unnoticed as his Yamikumo approached Bakugou.
Katsuki stayed back, ready to jump into action and do whatever he needed to to protect the boy. His eyes sharpened on the inevitable interaction and his hearing heightened as he felt his knife shift in his yellow cardigan, unknowing that Midoriya was watching his every movement.
“So, I heard you were quite the ‘angry Pomeranian’ 24/7?” Yami asked with a dark little smirk and back at the circle, Kaminari visibly gulped.
“What the fuck did you just fucking call me nerd?” Bakugou growled in response and Katsuki stiffened. Control slowing starting to slip away for the third time since he’s got here. No one talked to his Yamikumo like that, he took care of all of his bullies to make sure of that.
At those words, Yami stared wide-eyed with a huge smile on his face and seeing this, Katsuki was able to calm down a bit, still on high alert, but losing some of the bloodlust that had been building up.
“Wow...I have never heard those words come out of that mouth-” Yami started to laugh. “Go on, say something else vulgar.“
“The fuck? What’s so funny you stupid piece of shit-“ Bakugou yelled as he started to get up.
“Kacc-“ Midoriya tried to intervene before Bakugou did something he would regret, only to be interrupted.
“Can it Deku,” And at that, Yami’s laughter slowed to a stop.
He turned to Bakugou, face so serious you could of never guessed he was laughing a few seconds ago. “What’d you just call him?” He asked, a bit of anger evident in his voice.
Seeing how he got a rise out of the smaller boy, Bakugou smirked, “I called him Deku, what’s it to you?”
“Well I’m pretty sure that means fucking useless and he’s been way more helpful than you have the past few minutes I’ve been here so if he’s a Deku, what does that make you?” Yamikumo questioned, a dark smirk appearing on his face once more.
“WHAT THE FUCK DID YOU JUST SAY TO ME-“ Bakugou started walking forward in the direction of the boy and Kirishima went to stop him, laughing nervously, as Katsuki, snapping out his will to kill, went to stop his little gremlin.
Pulling Yami back towards the circle of friends, Katsuki was met with surprised faces and one embarrassed Midoriya Izuku.
"You really didn't have to do that Mikumo," Midoriya said, voice muffled as he hid his face in his arms.
"Yeah well, I know being called useless doesn't exactly feel that good from experience so," He replied, leaning back on Katsuki as he was placed back in his lap, knowing that he wouldn't be able to escape and just getting used to it.
"Aww, what do you mean? I mean, unless you don't want to talk about it-" Uraraka asked, about to apologize if she brought up a difficult topic, only to be assured that it was fine.
"Well Yami is quirkless," Katsuki started, watching the reaction of his Yamikumo to make sure this was okay before he continued and gaining the attention of the rest of the circle. "And he used to get bullied for it and stuff in middle school when I wasn't around to protect him," and at that, Yami started to blush again.
"Oi, stop making it seem like you're my guardian angel or something" He murmured, causing Katsuki to laugh and smile, the mood in the room brightening a bit. "Well I kind of am~" Katsuki replied, dodging the elbow that was once again, flying towards his stomach.
"Anywho, it doesn't really matter because my Yamikumo is going to be one of the greatest heroes out there!" Katsuki finished and Midoriya looked up from his notebook, where he had been writing all of this down.
"You mean, Mikumo passed the hero course's entrance exam without a quirk?!?!" He asked surprised.
Katsuki's eyes sharpened, he didn't know why that was so surprising. His Yamikumo was amazing, he could do anything and Katsuki would always be there to help. Of course, these guys don't know much about the two so Katsuki decided to let it slide just this once and explain. "Yeah, at our school there are 3 different entrance exams, one for elemental and long distance quirks, one for more physical quirks, and one for mental quirks. I mean, it'd be kind of unfair for everyone to take the same kind of exam when there are so many different abilities. Believe it or not, my Yamikumo was way better in the physical exam than most of the people there with quirks~"
The circle stared at Katsuki in some mixture of shock and awe at this information and Katsuki stared back. Yami, being the person he is, had fell asleep in Katsuki's lap and complete silence surrounded the group until someone spoke up.
"That is so unfair" Uraraka whined after a while, "We all had to fight giant robots."
"Oh my god, it was so exhausting" Mina chimed in, and the group started laughing, not too loud to risk waking his Yamikumo though, which Katsuki was grateful for.
After a few minutes of mindless chatter, the black haired man from earlier finally returned, beside him, a....walking animal in a suit? The mouse-bear thing started towards himself and Yami while the man in all black stayed at the door, surveying the state of the classroom in his absence.
"Ah I see, this is absolutely fascinating..." As the animal approached Katsuki and one sleeping Yamikumo, Katsuki sat there shocked.
"Hello Katsuki, I'm Principal Nedzu and the man by the door is Mr. Aizawa. I hate to interrupt, but I need you 2 to come with me to Recovery Girl if you don't mind," Principal Nedzu said calmly, with a smile on his face, though something seemed a bit off.
"Alright," Katsuki sighed, picking up Yami to carry him bridal and leaving the room with the principal. Instead of picking up where they left off, Aizawa entered his sleeping bag, seeing how class was almost over anyway.
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Once the Katsuki and Mikumo were gone, the group fixed the chairs and tables and Mina, Sero, and Kaminari left the circle to go a join Kirishima and a still very angry Bakugou while Uraraka went to join Tsu, Yaoyorozu, Hagakure, Jirou, and Aoyama.
Izuku was left continuing to sit though. With all the notes he had collected, he had a pretty good idea of how Katsuki (it felt so weird saying anything other than Kacchan) and Mikumo got here.
Going through his notes, Izuku started to realize how similar Mikumo and Katsuki's relationship were to his and Kacchan's relationship, and by similar, he means it's like the two are complete opposites. Katsuki looked exactly like Kacchan and they had the exact same names but they acted completely different from each other. Katsuki was happy, nice, probably a bit over protective, and very supportive of Mikumo although he was quirkless while Kacchan was basically a bully who thought Izuku was weak and useless when he was quirkless, and still thinks so even now, though he has a quirk.
Mikumo looked really similar to himself but had messy purple hair and red eyes and acted like he didn't appreciate the company of Katsuki when it was obvious that he did, while Izuku cherished any moment he got with Kacchan where he wasn't being yelled at, laughed at, or hurt.
If Katsuki was supposedly the doppelganger of Kacchan....then maybe Mikumo is the doppelganger of him. Either this was the work of some weird copy quirk or Mikumo and Katsuki really were from someplace else.
"Another world..." Izuku thought to himself, before getting up to share his theory with Todoroki.
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"Well, the blood samples say that they're real and Aizawa used his quirk on the blond one and they didn't melt so it's semi-safe to assume they're not directly working for the league, right?"
"We're not certain, Tsukauchi has been called in to interrogate them although, I'm quite sure I know what we're dealing with already!"
Toshinori and Principal Nedzu stood side by side outside the door of the Infirmary, watching the two boys that had appeared in Class 1-A and Recovery Girl interact from afar.
Toshinori directed his attention to the principal, wondering how he could have figured out whatever happened already, but not surprised that he did. "What do you suspect we're dealing with?" He questioned, rather curious for answers himself, and Nedzu smiled.
"While right now it's basically just a hunch, I have a feeling we're dealing with the result of an alternate dimension quirk!" Nedzu explained, his usual unnerving smile not changing in the slightest, and Toshinori's eyes widened.
An...alternate dimension? Just the sound of those words felt so unreal, but when he thought about it, that was most definitely something to consider. "What makes you think that?" he asked.
"As I said, it's just a hunch," Nedzu replied, and they both stood in silence, resuming their observations of the newcomers.