Kimi to Nara, Ashita wo Utaeru no

A high school student who is well-liked but struggles to express her own feelings meets another girl who sings and plays guitar. After encountering her, she finds herself humming the same tune in class, only to be approached by the girl, who reveals she is a student at the same school. The girl claims to have come from the future to save her. The two girls develop a connection that changes the way the first girl views herself and her relationships.