Explanation of Deku's quirk:

Izuku is born with a ,quote on quote,"villainous" quirk and one day snaps from all the bullying. Soon after he meets a girl with a pretty similar quirk and story,the two soon find themselves in a league. How will things develop from here? You'll have to wait to find out.
Don't worry,I'm not ending the other story just writing this while I think of what should happen in that story.
Takes a bit to get to romantic feelings,just a heads up.