>>2450618Different anon, but to answer you; Shinsou's been picked to the scapegoat kinda, becasue for some reason, even though technically any of the students can use their powers for evil (like how Bakagou can explode a bank vault and rob a place, or Tokoyami can go on a killing spree with Dark Shadow) he's been ostracized with this brainwashing to be seen as the bad guy. Even though he's never done anything bad (as far as we know!), everyone associates his quirk as something negative. Really it's becasue children are dumb and think that mind control automatically = villain. Like telling the good guy to jump off a bridge, or trick a teacher to giving you good grades, whatever the case, it's always negative. Nobody really thinks about how he can be the one to STOP the villain by brainwashing them into putting down the gun, or working with the police force as a hostage negation person. If he's constitutionally being tagged as the bad guy or just a weird guy people don't even want to talk to for no other reason than "because your quirk can only be used for bad". You can imagine he kinda grew a little chip on his shoulder becasue of it, especially becasue he really, really wants to be a hero. He's Deku's mirror opposite character; While he was born with a quirk, it's not a physical one and he's been branded as the leper.
So instead of working to make his quirk more powerful, maybe he avoids using it, as
>>2450399 mentioned cause he developed a complex about it.
I also second this fic idea btw, and I would like to suggest he gets molested by an unknown, older stranger in the alleyway. 'Tis my kink!