This is a mod that adds several perks and spells related to the player playing while wearing chastity devices and on placing nearby enemies in chastity. The gameplay takes the themes of the Trainee class but is not wholly dependent on them to engage with. 
https://enraa.itch.io/chastity101

Great mod - but sometimes has a bug where you get multiple notifications about chastity keys in the item description.

Also, late-game, Chastity keys seem to be super rare.