Recs if you like Never Fall for a Dragon (Mate Mountain, #1)...

Limiting this to fantasy/sci-fi, these are books where the MCs are locked up for most of the book or it's a crucial part of the plot. This can include magical prisons, cursed towers, institutions of sorts, and probably more!

For those monster lovers who want the things that go bump in the night

Ogres and aliens and tentacles, OH MY

Demon, dragons, werewolves, bears, magic and shifters. Lola Glasses Supernatural Prison World