Obviously this was all the fault of Katsuki's perv classmate and his aerosolized heat trigger. Once Katsuki gets his life back under control, everyone will forget all about this moment of weakness. Nothing will change. He won't let it change. After all, he's going to be the number one hero one day. Just because omegas never go pro, that doesn't mean it isn't possible, right? ...right?

Kirishima tries to help Bakugou out during his first heat, and things get complicated.

It's involuntary the way his knees seem to buckle and give out and throw him onto the ground. It takes him a moment to realize he's hyperventilating, tears running frustratingly down his cheeks as he rubs his clothed erection slowly against the carpet. / Or the one where Bakugou Katsuki is presenting as a fucking omega, and there's nothing he can do to stop it