Haruta Maho (Yoshida Mizuki), a hit manga artist, time-travels back to her high school days. She tries to help her senior in the manga club, Yukishima (Fujiwara Itsuki), make his debut as a manga artist, but he collapses earlier than he remembers before the time-travel... As Maho sorts out the timeline to solve the mystery, she suddenly returns to September 1, 2015. In her second time-travel, she proactively solves all her previous mistakes, but Arashi (Okura Sorato), a member of the student council, sees Maho and becomes suspicious.