The game in general is nice but there's 3 things that I belive could be improved.
The first one is the physics, they feel "slippery" wich is not bad but are hard to predict, for example in the original watermelon game wich has those "clasic flash games" balls physics it's easier to understand them.
Secondly, results hard (at least fot me) to realize the correct sizes of the hitboxes, correct me if I'm worng but I belive that Sana has some sort of hitbox under her that makes her float a little bit above other girls.
Thirdly, please add a functionalitie to manually decrease the volume of the game (a volume bar or something like that) I had to reduce the volume of my PC to the minimum because the game was very loud.
I belive that you can make the game better by doing some small updates, looking forward to it :D