Not a bad one, but outside of hex girl, I guess all you can do is masterbate and play with her breasts?
Pretty much, the presentation and music also adds to nostalgia especially if you grew up playing the GBA era like I did.
Joi is the name of the game (Jerk off instructions) and that's something me and a lot of others are into. If it's not your thing then you at least didn't put any money down on trying a new experience but I hope you did enjoi your time playing regardless.
Side Note: I plan to do more with this concept in the future and add more interaction + responsive elements but I never want to pump these games out so that each one feels unique like your interacting with a different character IN character and not just interacting with a popular character with generic writing scripts.