I would like to keep them as servants, like teach them how to clean and chop wood and stuff. Use werewolves as guard dogs, wererats as housemaids and lizardmen to help with the garden or something like that and reward them with food and sex. I know it sounds like slavery but it´s way better than put them in a cell to rot. Or maybe hold them in the prison in order to cure the curse of lust or give them the antilycan. But maybe for future development, I'm more interested in the plot and every new character and species than anything else.
Well, maybe some players are not into that, the same way some are against dating multiple partners. In the game you literally kidnap this creatures from their habitat, then throw them in jail and visit them in order to take advantage of their lonely horny state. If on top of that you put them to work for you just because you can, it kinda sounds like slavery to me. Definitively doesn't sound like spa treatment. But hey, it's just a game and it can be played however you want. That's the hole point.