To be honest I did not play nor watch any content regarding Exp 33 so I have no idea how much this is inspired by it, but the overall concept seems interesting.
-----------POSSIBLE SPOILERS AHEAD IDK---------
As the post-content note says, the next update will clear up who the mc is. This is fine. But I still feel that there is so little we know about him. There are hints that the family is not his biological one, pretty clear hints, but they are easy to miss, and many players (definitely me including) honestly do hate actual in*est, so please before starting an actual relationship b/w MC and the blonde girl, please clear up their actual current relationship.
Also we know almost nothing about the other two girls mentioned? Sure they are supposed to be friends, but nothing more than that, and they only have one scene for now.
Personally, if you can manage it I'd also like a characters screen in the future.
These are my problems/suggestions. The game otherwise is interesting, if the first one is solved I will return for sure.