Oc/Reader Is Male. He is in his late 20s early 30s. He is straight.

His quirk is Speedster. It's lets him move at super speeds, Super stamina, Super Reflex, Accelerated Healing, Enhanced Durability, Vibrate His Body Through Living and Non living things. (Every thing they CW Flash can do In the early couple of seasons)

He is a pro hero called The Flash.

He is the fastest hero Alive, Being faster than All Might and hawks.

He is also extremely smart as His speed let's him read and think faster then everyone else. So he uses his speed to read thousands of books in minutes.

He is a Combat and rescue Hero, He has saved thousands from disasters using his speed.

He patrols the whole country when ever he is able.

He has his own agency That Has lots of People that have "Useless Quirks" working for him, they use their quirks to Monitor for people in need. He has no sidekicks as no one is able to keep up with him.

He is well liked by most other Pro heros , And he works well with the police.

He hates the Hero commission As they want him to do everything they say. (or something like that)

He Is the Number 2 Hero, Endeavour is the number 3 hero. (So endeavour hates him.)

Izuku has known him since he was a child as, when inko went into labour she was stuck at a villain attack, so the flash ran her to the hospital and stayed by her side while she gave birth as she Was upset. (or something where izuku has known oc/reader since he was a baby/child)

When Shoto Gets internship Invites he goes with The flash instead. And when oc/reader see the signs of Child Abuse he manages to get shoto to tell him everything, So he confronts endeavour and gets custody of shoto becoming his adoptive father. (or something like that where he adopts shoto)