The clumsy writing makes characters practically interchangeable other than the first time you meet them, and it clearly hasn't been proofread. Sleep/work system adds clicks without adding any gameplay, so it's just tedious. Characters are very true to their original designs (at least, the ones I checked out are), but in Koikatsu, that ends up looking creepy for some of them because the 2D art doesn't translate to 3D. So many opportunities to do interesting things with characters' unique traits and powers were missed, and some even seem to miss the point of the characters. (No use of Ochako's antigravity powers during sex? Not even an option to be a sub or masochist for Utena/Baiser? Just the standard negative reaction rather than horror from Wiz, an undead character harmed by anything holy, if you suggest going to a temple as a date?) It works smoothly as a gallery of contextless sex scenes, so it's competently programmed and the scenes were set up and captured to video well, but it's not much of a game in its current state. If this is a new developer, then don't be discouraged by bad reviews, but please try different things. If this is an experienced developer, please get help with the writing and advice on tweaking the character models to fit Koikatsu better.