BAND WO KUBI NI SARETA BOKU TO OSHI JK NO SEISHUN REWRITE

Just before their major debut, 26-year-old Shibakusa Tooru is fired by his bandmates. In the midst of his despair, he learns that his former classmate and favorite artist, Narahara Shigure, has committed suicide. With nowhere to turn, Tooru jumps off the balcony to follow her...or so he thought, but he suddenly finds himself transported back in time to his high school days. In order to change his terrible future, he must start over with his favorite high school girl in this school youth revenge story! (Source: Kadokawa, translated) — Description from AniList community (anilist.co).