All it takes is an accident (Villain!Deku)

the super hero festival

The next day, after Katsuki got over his initial shock he bombarded Izuku with questions about his quirk. 

Questions like "Can you pull it out of your chest? Or make different weapons like machetes or battle axes?" and "What about pulling it out of your hands or elbows or knees?".

All of which he tested and surprisingly worked. The only drawbacks/flaws were that large weapons like axes or swords had to come out of his chest while little things like knives or brass knuckles could come from his hand, arm, legs, and large joints. 

Also, he couldn't control it well, so if he ever got too mad, then a weapon would appear even if he didn't want it to. Once not attached the weapons would turn black, lacking their quirk steal element and making his 'useless'quirk more useful to him. He was happy but still practically traumatized about....

'Never mind that!' Izuku thought, 'I need to get ready for the super hero festival'. That day Katsuki and Izuku, being the big All might fans they were, were going to the festival to get as much Allmight merchandise as they could get their tiny hands on."Welp, don't get kidnapped and have fun at the festival" said Mitsuki as she waved at them while they left.

----------Timeskip my dudes(OOOOOOOOOHHHHHHH)----------

As the small children arrived they saw many top heroes walking around. Midoriya and Bakugo ran up to the entrance only to be stopped by a large man wearing a suit. 

"You kids can't come in, since the 18+ hero midnight will be here this time, come back next time".

.

.

.

Or at least that's what he would have said if the two didn't already sprint past him. The two kids, still sprinting, made their way to the Allmight section which was (obviously) the largest one to find the merchandise that they didn't have but not before passing the midnight booth. After finally reaching the Allmight merch stands they practically bought out the whole thing and decided to start leaving.

As the kids reached the exit, showing each other the cool stuff they got, a purple mist swallowed them both up and they appeared in an bar (shut up I know that the ages are wrong just bear with me. also mist guy is perpetually an adult cuz Y not?). They see a smol boi with hands littering his body and face and crusty dusty musty ass skin. He starts talking, 

"Hello! you must be the kids with the awesome quirks that Kurogiri was talking about. You with the sand in his hair, you must be the one with the explosive quirk and you ther-" Shigaraki hesitated. 

"Kurogiri, are you sure he he is able to steal quirks I mean, just look at him!" 

"Hey! I can steal quirks!" the agitated midoriya said as a brilliantly green spear stuck out of his chest a full meter in front of him . Shigaraki walked up and put a tight grip on the spear, but nothing happened, 

"Wow, it's not decaying, that's a strong quirk." he exclaimed

After Tomura bombarded Midoriya with the same questions Bakugo did, he asked a simple question,

"Do you guys want to be villains with me?" to which both of the hero fans shook their heads vigorously.

"OK well here's the address of this bar if you change your mind, and if you tell anyone we will have to get a little unfriendly" Kurogiri said while opening a portal to the exit of the festival.

Bakugo and Midoriya both went through hearing Shigaraki yell "SEE YOU LATER MIDORIYA AND BAKUGO!". 

They then were greeted by the same screaming body guard from earlier, and ran home. Once at their house they went inside, ate dinner and were getting ready for bed when Izuku asked Katsuki a question. 

"Hey, Kacchan, does this whole thing make me, you know, like your brother or something?"

"um, probably?" Bakugo said reluctantly.

"huh" he said, slightly smiling