You Belong To Me Fuutarou Uesugi-kun

From the best selling Manga series, Quintessential Quintuplets comes the horror, psychological story of Quintessential Quintuplets, Fuutarou Uesugi is been traumatized by the murder of the Nankano sisters leaving Itsuki, the only Nakano sister alive. The death of the sisters were a big mystery. Fuutarou returns as a teacher and faces someone who resembles the killer