Lets see.... you took my favorite anime/manga and made it a dating sim.... thank you a lot mate(not sarcasm).
The minigames are nice excepting some bugs and hte act they become really easy whith a lil time.
The dating system is really nice and the fact you cant give the same gift twice its just magnificent.
The history is nice, you kinda follow the original (not that it is really necesary) but i think if you could see the calendar maybe if you had more events or maybe just making them more compelex or umpredictable would make the gameplay a lot better. If you want to see some reference i think you could see the last version of sim girls, since your style reminded me a lot of that game before it was finished (wish took yeears).
About the sexual part, some people have told you and i agree that you should make it diferent for each girl so you give us a motive to get them all (gota catch them all!).
The artwork isnt good or bad, i know not much of programming but i guess the animations may take a while and a lot of effort. Anyway i think if you upgraded the animations it would make a huge difference.
Overall one of the nices games i have played here and i hope to see more of your work soon, sorry if i was too hard on you but it is just because i see so much potential in this game....