The game has nothing to do with slaves, but with girls (or boys depending on the sexual choice of the protagonist) who fall in love with the protagonist throughout the story.
This Harem would have characters clichés of animes like: the angry girl who likes the protagonist and does not admit that likes him, the girl who is too shy to reveal his feelings for the protagonist, the cold girl who seems to have no feelings but proves to be one of the kinder people that the protagonist has already met or even a yandere.
The best of this theme is that I can use this in any kind of story. (I’m thinking of making a superhero game with this theme since I’ve never seen anything like it)