I gave this one a whirl and tbh I like what's forming up. Love the Captivity aesthetic and style of characters, and the ambience seems really nice, the dark fantasy where people live in caves is a nice setup for your own world to create.
Gameplay wise, I like the concept of serving and such with the ocassional sex-favor to make some extra cash. Right now there are a few things that I think could be tweaked, like the looong time it takes for the character to stand after getting tripped and falling over, or how little sexual favors can pay you, personally I think you should be paid a tiny bit more to make it more worth your time than just serving alcohol.
Regarding on that topic, I suggest the idea of allowing the player to pick up empty cups/bottles with the tray, because otherwise it can be a tedious task to run back and forth with a single bottle.
Personal suggestion based on my taste regarding fetishes and stuff:
-Pregnancy.
-This game would do nicely with it in this dark setting as civilization needs to replenish numbers . You could have a set chance when doing vaginal sex that could increase or decrease with fertility items or conraceptives, and after a few weeks of game your character will give birth to a random number based on the race of the father. The tavern owner could offer you to sell the baby to him (or hell, maybe give you the option of paying if you get pregnant from a specific client ) or you could try to keep it at the cost of having a slightly higher weekly rate. Another more common option is implementing a nursery of sorts where your offspring is accomodated there, kind of how CoC/TiTS does it and just keep offspring as a number while keeping pregnancy relevant for the folk who are into it.
Looking forward to seeing how this project will develop! Cheers!