After Izuku almost died from the sludge villain and All Might told him he couldn’t be a quirkless hero Izuku surprisingly didn’t give up. Instead he changed course. He became a vigilante instead but he had a legal loophole because vigilantism is illegal, but since he technically doesn’t have a quirk, it isn’t vigilantism. About three months after Katsuki had been in UA Izuku had been a masked vigilante for like six months. About two months ago Aizawa found Izuku and is now basically his mentor. Izuku is also friends with Tenko, Touya, Himiko, and Kurogiri. Because Izuku wasn’t aware of who All For One was other than the fact he was bad so Izuku destroyed AFO’s life support stuff and then Tenko, Touya, Himiko, and Kurogiri showed up and Izuku somehow convinced them to stop being villains. Hitoshi is Aizawa’s adopted son. And because Izuku often crashes at Aizawa’s house Izuku and Hitoshi are really good friends and Hitoshi asks Izuku to take on vigilante missions because Aizawa would kill Hitoshi if he was a vigilante.