YOUR OSAMU DAZAI, AND YOUR OLDER BROTHER IS SHOUTA AIZAWA AND YOUR OLD NAME IS SHŪJI AIZAWA. When Shouta was 6, his mom had his younger brother, Shūji aka you, growing up the two brothers were extremely close, Shūji was supposedly quirkless, when in reality he had an ability, an ability is the original quirk, and it’s much more powerful and more rare, but you nor your family or anyone else knew that, you being quirkless and powerless stuck, Shouta did everything to protect you