This is game's story was probably one of the best things that came out not only in 2020, but in the last decade that preceded it.
With already 21 main characters (counting MC) + more side characters, every single one is not only clearly distinguishable, but compelling at the same time. They all have their flaws, some more obvious and downright (morally) unjustifiable, but even then, you can find something relatable in them to some degree.
I keep wanting to know the girls better not just because I have to in order to continue the main story, or because they are so well written, but because they can make your day a happier one. Simply put, they are cute as fuck, and them being happy is joyful, until missery unexpectedly rears its beautiful ugly head.
This game requires you to advance the girls' events in order to continue the main ones, but I think you should do it even if it wasn't the case. Never skip on girl's event or dialogue. Even if you didn't want to do her story for whatever reason, and only wanted to do the ones you liked, you never know when a hint or piece of the puzzle that is the main story will drop. Its never just the characters geting development or going on with their lives, but they are essential to even know what is going on below behind the scenes.
Without giving out spoilers, thats my review for the story part. For the gameplay part:
It works as a standard VN to a degree. After your first events, you get freedom to go where you want from the options. Of course, all these options involve calling them to hang out, inviting them home, or visiting a girl in either their shared dorm room or their "usual spot" (work/club/streets where they just... walk).
The more common is the last 2 forms of visit, since calling them or calling them to invite them home isn't available until you get the girl's phone number. You only get that in either the girl's event in question, or unexpectedly in an almost unrelated event.
Either way, the most predominant way to unlock the girls' event is getting 5 affection points each time by visiting them.
One important part is that there is not hint system. And since some events are locked not just by points, but by interacting with the girl in question in a specific way at a specific time.
For example, visiting a girl on Monday in her dorm room. or calling them on Saturday afternoon.
Thankfully (MC would disagree) those times periods are reduced to only the evenings from Monday to Friday, with only the weekends having Morning-Afternoon-Night time periods.
The problems to find these events is reduced by the fact that there are 20 main girls + the side ones, so you will end up circling around unlocking events for the other girls until you coincidentally hit ther giht combination.
If you just do as said, and progress with all the girls, you will rarely find an issue.
As of v0.17.0, the girls, our relationship with them and the world itself has changed. Some changes are more subtle than others, but they are there once you compare them to the first releases. And these subtle changes will keep on piling up for the next years as we get more updates.
Even if VNs, or adult content in general isn't something you particularly enjoy, you should absolutely try this game.