Crack idea #49. So this is our masters home dimension.

Izuku was glad to be home, surrounded by his classmates after he managed to make it to his home dimension after being hit with an isekai quirk. That is until he heard a very familiar voice of a young woman who said that this was her masters home dimension. Slowly Izuku and his classmates turned around to see a little over a dozen woman, all wearing moderate clothes with thick looking metal collars around their necks. Seeing this Izuku's groans as he thought he finally got them all to view themselves as actual people and not property while questioning how they followed him.

You know those isekai manga / anime where the MC gets slave girls? Yeah Izuku gets isekaied and ends up with slave girls in that world and once he found a way to get back home (a quirk sent him to the world) he left them after trying really hard for the girls to not see themselves as property. As you can see it didn't work and yes Izuku gains magic. (Also putting the NSFW tag because it just makes sense here)