I dont think this is the first time i read stories of confinement. But i guess the 2 that i can remember from the top of my head is that one manga about a white haired dude kidnapping a girl who was abused or something. Then if im not wrong theres a second series of that one about the investigator that was investigating them. The other was the mangaka that was confined by a fanatic fan of his. The girl was the streotype where she likes wearing lolita/gothic clothing or something.
Anyways, for some reason only this one actually reminded me that i had these kinds of fantasies when i was a kid. Confinement and restriction. I guess this one's inclusion of sex is what made it clicked huh. But the gender is reversed. Me used to dream of confined animu waifus with the mc. Never the reversed.