This does has a lot of potential. I do like where it's going I do have a couple of things to note.
Firstly, the map is something I hope you change. Not being able to move freely from one barely labeled room to the next was pretty disorienting, but it isn't as much of a problem this early in development when there's little to do. But anything more than what you have, and it's going to get pretty confusing real quick. I would take a look at something like House in the Rift or Hero's Harem Guild for guidance; as much as they're both on Renpy, I think the direction they take to show what is interactable and what isn't is something you take apply to this Unity project.
Another thing those two do well (especially HHG) is having a likeable main character. I get turned off so quickly from an H game if the MC sucks and is cringe or awful or whatever, and I was worried I was going to feel the same way for Den. Thankfully, I do like him, and I hope you can expand on his relationship with this family. I think he and Raven have good enough chemistry, and I can imagine that you'd want to have somewhat of a greater build up to the Unlyfans shoot down the line.
Something I do hope you change is the models. This last note is the most hesitant, because I don't know how much time or effort it would take to alter the gifts bestowed by scrag_boy. I also think that having different body types leads to a more interesting adult vn, both visually and narratively. I love girls with small tits, just as much (probably even more sometimes) as I love them when they're big. I think a perky ass can go a long way to develop someone's character. Could Sierra be jealous of her sisters for their more profound features? And why doesn't Zoe have MORE muscle? Her arms and legs look identical to the rest of her family! This isn't to say that you need everything to be realistic, because, come on, it's a porn game. I just personally would like to see different styles, because beyond the obvious fact that these models are from different franchises (it did threw me off seeing Daisy for the first time, but I think you recognized that), there isn't that much to physically differentiate from (currently) Zoe or Raven.
Then again, I also don't know what you have planned. I don't have Patreon, OR Discord, OR Twitter. I mean, I do, but you know.