After the first time Monoma tried to copy Eri's quirk and failed to do so, he had offered Aizawa-sensei to be her babysitter whenever Mirio –that now's a pro hero while you and Neito are on second year– is busy.

You never saw a problem with it, but today at the dorms, he suddenly pushed your door open, and once you looked up, he said with a stoic dace:

"Please give me my own Eri us' version."

He came back of his babysitter day with a terrible baby fever. You're both eighteen but damn Monoma!