First off, I want to praise the game for being compact in size (<100MB), which seems to be a rarity these days. Though, this is of course just a detail. More importantly, the art style is fairly charming and all the sex scenes are done well and feel satisfying.
Each girl is somewhat unique and interesting. Unfortunately, the same can't be said about the progression system. It functions identically for each girl: text in class -> meet after school -> move to hideout -> ending. This makes the game feel rather repetitive despite being a very short experience as is.
The translations were good enough to get the point across and the writing wasn't lengthy, which I like. Another good point is that you basically get to sex immediately, once you figure out the controls. This however brings me to the biggest downside, as others have already pointed out. The UI is terrible. It's one of those cases where prioritising aesthetics has hindered the functionality of the game.
Very often, you'll be fiddling around the screen, trying to figure out what to do. For example, it took me quite a while in the very beginning to realise that I can click on the MC to reach the bubble "Text her." Likewise, at another point, you're required to have sex with a certain girl in a very specific manner in order to progress, and none of it is clarified whatsoever.
Lastly, despite of finishing the main three lines and unlocking the 4P mode, I still haven't found out how to save your progress―and whether that's even possible at all, which should tell you just how bad the UI design is. Overall though, I can't completely knock the game since you're basically done with it in like 2-3h anyway. So it's a fun, very short experience with some minor frustrations along the way.