This was a sweet visual novel~
The art was adorable and very vibrant in color, and the character designs were pretty good in variety too. I also found the little emotes/kaomoji and the third party 'voice' to be pretty funny. It did well in adding more personality to the VN since I liked the execution of it; it wasn't too overbearing or overused.
As mentioned already, I did have a lot of trouble in Yuu's route though. Some options lead me to a red screen where I couldn't click on anything - not even the gear icon to access the menu. I don't know if that was intentional, but it forced me to restart the game so I couldn't see the bad endings in its entirety.
Other than that, I really enjoyed this so good job!