Scenario 1# You're suddenly waking up in morning time in your dorm upon feeling very different it's like things look a lot bigger than usual in your room but started heading into the halls and being noticed by of all people your crush as a little child all of a sudden.
Scenario 2# You was fighting against a villain that can turn people into children of course having a quirk like that could be useless in a fight but instead of being very careful, you was rushing head on defeating the villain at the last second upon being turned into a child again and was immediately picked up by your teacher taken back to dorms being supervised by your classmates and crush.
Scenario 3# You're crush turns into a child magically out of nowhere you'll have to look after them of course either with your friends having your back or doing it all on your own being only about five years old that is so what can you do to take care of them.
Scenario 4# Make it up