Wait a cotton-picking minute - how come the protagonists rooms is the same as the one in School of Love? (have I been playing too many VNs?)
Koikatsu is what the characters are made in. IT's a dating/h-game but includes the ability to make custom characters. It also includes Charastudio, which is where all the renders are made with the poses, animations, scenes, etc. If you search Koikatsu Party on steam you can see the steam version of the game.