If you’re open to a platformer, the only explicitly adult game I’ve tried is FlipWitch. The gimmick is that you can change your sex, with certain obstacles only able to be passed through by a specific sex. You also have clothing that can only be worn by each sex, and certain NPCs won’t interact unless you’re wearing certain items. It’s a solid metroidvania, and while it’s not going to blow you away, I still enjoyed my time with it.