Note: I watched AlphaBetaGamer's video on the game, and so I can't speak to how it feels from a gameplay perspective.
Very, very charming little game! I'm a big fan of the art style too. My only critiques would be
- The best ending feels a bit... flat. It feels like you enter that confrontation, and then we're kinda rushed to the end.
- I'm a bit wary of Greta's "feels like there's another inside me" deal, just because of how demonized DID is. Unless I'm misunderstanding and this isn't meant to be relating to DID, and is more about her having unstable moods (understandable in a Monster Family).
I know that the sexualization of Alesa is a bit hit or miss for people. Personally, I don't mind it. As you've said it's a homage to horror movies which quite often use this (whether it be because sex sells, the fear of being preyed on in our most vulnerable states, etc), and I feel it adds a cheesy feeling to the game (not a bad thing. Silliness and cheese can be wonderful).
Lovely game. I hope your future works go well, and more importantly, I hope you'll recover well.