I'm working on a dating game/rouguelike dungeon crawler hybrid. There are only four characters for the sake of simplicity but this could easily be expanded to include more body types and kinks and identities.
If you treat them well enough when adventuring; talking to them often, asking them if they want to go down to the next level or need to take a break you will be rewarded with some NSFW artwork.
All the dating hybrid games I've seen are puzzle games and you have to just memorize trivial facts about your partner. I like puzzle games but it doesn't really fit the theme??