I read this manga a long time ago and couldn’t remember the title. It’s about this mc who made a deal with the devil(?) and went back to the past to save this girl (long hair girl). She died in the future, so he went back to the time they’re still in high school. I remember that there’s a handsome mute guy who is the girl’s childhood friend. He tend to write down his thoughts on a piece of paper/notepad/whiteboard (can’t remember much) There’s also a short hair cheerful girl who also went back to the past to save the girl.

Hensokukei Quadrangle?

Yes that’s the one! Thank you so much 😊