Izuku got hit with a quirk during his mission. The quirk didn’t had any bad effects but it ended up splitting his personality in half. His normal self and the opposite of him, who is rude and cocky, they were talking and a bit of arguing

Izuku: “Hey! Don’t say that, that’s mean” He said to the other

Rude Izuku: “And? I don’t care” He roll his eyes