The fourth play in the 'Heli-X' series. When Sadness woke up, she was alone in a dimly lit place. A small ray of light illuminated the knife in her hand. When she looked at the ground, she saw a large pool of blood and a motionless body... A corpse with a face she recognised. Was Sadness the one who killed them?
Youth suspense story where Ren Ozawa, who appeared on various popular stages and acted as a variety program and voice actor, serves as a high school teacher for the first time. An incident occurred on Valentine's Day when a student died due to poisoned chocolate. The teacher, Nishina (Ozawa), who is cold and ridiculed by students, tries to unravel the truth