Looks good. I'd say it's giving me "3d model" as reference/trace vibes though. This is one of those ironic times that the imperfections of drawing completely by hand actually lend art that special something. I'm not suggesting you do all your art that way, since you have a schedule to keep and don't want to burn out, but the kind of stuff that'll push your art to the next level is to add small details at focal points; that is to say where the viewer's eyes will be. For almost any drawing of person, the hands and face are what people look at first, and in porn, of course things like breasts and butts and such. I'd say keep tracing/using 3d models as reference, but to actually draw the hands and faces yourself, merely referring to the reference for things like proportion, foreshortening and perspective.
For the facial expressions, try to go a little bit farther than what seems natural/appropriate (like 5%-10% over your initial instinct), because what happens with stylized art is that you lose a ton of micro-detail that even the smoothest real human faces possess. The kind of stuff that allows us to see micro-expressions, those fine, nearly imperceptible minute details. Since cartoons don't have that kinda detail, masters of cartooning use the limited anatomy they do have access to and exaggerate it in a very deliberate way to precisely evoke an expression. Eyebrows, eyelids, and mouth shape and the relationships thereof, mixed with posture is the bedrock of expressive cartoony art. For your character, she looks bored and uninterested, because her face is almost neutral in expression, like fucking is as interesting as picking what kind of milk she wants in her coffee.
The way I think of it is an economy of expression, to efficiently as possible tell the audience what this character is feeling. If she's turned on, draw her turned on. Unless you're fully animating the scene, you'll have a very limited opportunity to get across the mood and tone and vibe of a character, and to make them feel like a person. And when it comes to smutty games, that is incredibly important, because otherwise people could just go to look at animated gifs or photos instead. They want that emotional context and character acting, that storytelling.
I'd also reccommend studying real photos as reference for how flesh/bodies behave. The breasts here look like bolt ons, honestly, because real breasts are basically bags of fatty tissue with very little rigidity in them, so they are conform to the forces of gravity unless acted upon by something (like a bra or a pair of hands). These are kinda gravity-defying, which is a telltale sign that an artist is simply posing a 3d model and using that as their foundation. Study cartooning, especially facial expressions. You'll find lots of references on how to do it.
I hope this helps, I have faith you can turn out a great, memorable game.
