This SIM was both very good and entertaining. Though there are a lot of room for improvements for entertainment and mechanics.
Pros:
Fun, colorful, and diverse characters
Various types of interactions depending on your 'heart' status with the characters
Different Endings long as you look for them.
Very Simple to grasp and understand that you don't need a long tutorial to get into the dating sim and characters, though is works against it too and I'll explain into more in a moment.
Stuff that could be made better:
Due to simplicity (which is good for base), there is a need or wanting for more from all the characters and not just the main four. This works against it with the hopes of finding events while juggling the studies and keeping up troupe goals like Harem Endings and such.
Characters - Because you may or may not get into the character quickly, there is a somewhat need to hit events for such characters or extend the events they already triggered. Like say one of the girls ask you out to the cafeteria. Extend the event a little more. Or if your using the eat button and you somehow trigger an event due to hitting a few points with another girl. I notice some of the girls supposedly give you chocolates or homemade food... I would like to see some interaction with that if possible in future games.
Health mechanics - there must be a way to improve 'stamina' that you can really get the must out of your health and such. As it seems that a single does not fully restore your health. So you're in a slight bind to micro-manage your stamina bar, studies, and wooing the girls around you.
Money gains - I understand that you're not expected to make it rich, that's fine, but I think the constant need to manage your funds with between eating to keep your health up and gaining enough to gift the girl or girls you like is a bit tough.
Keeping Track - The only way I knew I was doing okay with studies was constantly talking to the vampire teacher. Which is a decent and interesting way to know where your 'knowledge' level stands but it does get repetitive and at times you really don't feel the progression.
Skipping Conversations - This maybe a bug, but I notice there was a skip option but the option didn't last long on the screen and it is also not that very noticeable. It would be nice to have a skip option available all the time, even if it means we accidentally press it and miss out on new content.
Gallery or Achievement Collection - Maybe something to keep score of our achievements, maybe stats, the endings we get, and other miscellaneous stuff as we progress through our school life. It is nice to keep record of these things.
Length - I think one month time in game was too short, but that is just my thoughts on it.
Overall:
Game was a fun time killer and definitely been replaying it a lot. I look forward to your future games and I hope this review of mine is helpful to you and not made me sound overly critical. I always want to see the things I like become more better than before.
Cheers-
Markmoonedge