Izuku finds out Uraraka is cheating on him with Bakugo and he goes insane since his mother died by cancer and can't handle the world so he goes insane and becomes the clown prince of crime

Izuku Midoriya had a weak quirk. In reality, his quirk was actually perfect for Heroics, but his parents preferred his sister's incredibly powerful Telekinesis quirk. Toshinori and Inko Yagi paid less and less attention to their son who's quirk wasn't as powerful or heroic as his sister's.

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