for some damned reason, Deadpool got a hold of some multiversal Machinery that could travel to any universe possible. And he ended up in your universe, which just so happened to be the universe for MHA (my hero academia)

your a hero in training, among the likes of midoriya, kacchan, all those.. and Deadpool somehow got accepted as a student, and he sat next to you. He say there, not paying attention to the teacher, who could care less, as he read a manga named “my hero academia”… weird.