tl;dr: 4/5 or maybe 4.5/5, depending on your tastes.  It's worth it for the story and character stories.
Story
It's not a brilliant story, but for the setting, context, and structure, I can't really fault it too much.  The plotholes are pretty obvious once you see them, but it's the kind of story where it doesn't matter.  It starts off being told exclusively from the perspective of the main character, but slowly shifts to being told by refracting the world (and state of affairs) through those around you.
The individual character stories range from 'eh' to being quite interesting.  It's not a masterpiece, and the cast is too broad to really get much focus on more than one love interest, but there's enough there to sink your teeth into, and for the length/depth of the game/story, it's fairly well done.
The game is well worth playing for the story, but you need to really hold out a while at the start, because it's a really bumpy opening.
Structure
The structure is a fairly significant mess, but this was clearly a learning experience, so I'm writing this out to help those struggling to get through it, or those wondering.  The story (and character stories) make this worth playing, this is more a warning.
The game is divided into three 'chapters' (I believe they are all four parts each), plus an epilogue (which is one part in length).  The epilogue is required to complete any story (other than a 'bad' ending), so it's not really an epilogue (this is a minor gripe, but it helps to know that you'll be playing that part if you want closure).
The division of the three main 'chapters' is odd.  The first chapter opens very slowly, and its pace gets to a decent place right towards the end.  The second chapter is overloaded with lewd scenes/activity (you can opt out but it limits interactions).  The third chapter is way too fast, feels incredibly rushed, and I was seriously considering marking the game down to 3/5 over it.  The epilogue is probably the best paced part of the game, but it's one part, you know it's the end, so it's hard to credit it too much.
Graphics and Lewd Scenes
I won't give a score for this, because I never do.  But the graphics are sufficient, do improve over time (as with most games), and the lewd scene count goes from an appropriate amount (as you find your way through living with people) to an utterly insane amount (chapter 2) before dropping back to being excess to the needs of the story (to the point where it could possibly derail your attention at times).
Overall
It loses the star because of pacing, writing, and an increasing number of typos/grammar issues, which make it increasingly frustrating in arbitrary patches.  Considering its age, the graphics are good enough to not need marking down, the soundtrack/setup is fine, and the story is more than good enough to make it compelling.
I'm rounding down from 4.5 to 4 mostly because of the structure/writing issues.  The grammar is generally tolerable, but when the writing and pacing it get bad, and the conversations start to sound like it's the same person talking with a different name being shown, it really hurts the experience.  Each of those issues is easy to ignore/forgive in isolation, but there are a pockets where it gets so bad that it's a serious problem.