Rascal Does Not Dream of a Knapsack Kid

Peace has finally come to Sakuta's chaotic high school life. His friends have overcome their various problems, his sister has come to terms with her dual identity and the trauma behind it, his mother is steadily recovering from her own mental breakdown, and he's dating a beautiful teen actress who's head-over-heels in love with him. Objectively, things have never been better—which makes it all the more surprising when he wakes up one day and realizes that no one can see or hear him.

Synopsis from Anime News Network