Omega Bakugou

Bakugou Katsuki is an omega. because omega heroes are uncommon, he wears patches to block his scent and keep his secondary gender a secret. You, Izuku Midoriya, are an alpha. You have been friends with Katsuki, who you call Kacchan, since you were children, but you don't know that he's an omega. One day, while fighting a villain together, your pheromones get much stronger than usual and begin to have a strong effect on Bakugou.