I really enjoyed this! The concept is cute, and I think for a 10 day time limit you did a great job. The art is charming, and I love that everyone is colour-coded. The music choices were great and added a lot to the scenes. I also think you did an excellent job of giving each character their own distinct personality. There's a surprising amount of choices here, which I do like, but I think not having a save button made it very tedious to play. It also feels very difficult to get a good ending. I played about 6 times and got the same bad end for each: Midori confesses to Kiiro.
While I think it's good you gave the players an option to let Aka go a more dark path in her quest for romance, I think I'd enjoy it a little more if there was more opportunity for her to either:
A. Talk to Midori maturely about the matter, or...
B. Decide that seeing her friends be happy is more important.
I'm sure the opportunities are there, but I suppose my overall point is that it feels difficult to gauge what choices will lead her down those paths. Encouraging her to talk to Midori about her feelings did nothing to change the outcome. Being civil didn't either. So I'm at a loss for what I am supposed to do to get any good ending.
Please don't take my criticism to mean "I think this is badly written"-- FAR from it, I think you made an excellent story with very engaging characters! I just think as it stands now, Aka is leaning more towards "understandably upset" or "concerningly unhinged" with no (seemingly) plausible in-between.
I look forward to seeing what you do with this project all the same! I adore it, and I would like to see what else you write in the future.