In Musashino City, a mysterious figure known as Shounen Bat strikes fear into the hearts of its residents. With rollerblades and a golden baseball bat, this enigmatic assailant remains elusive and incomprehensible. Suspicions fall on Tsukiko Sagi, a reserved character designer, as the first victim. Supported only by her plush companion Maromi, Tsukiko becomes entangled in Shounen Bat's sinister web. As the attacks escalate, detectives Keiichi Ikari and Mitsuhiro Maniwa launch an investigation to unmask the perpetrator. Yet, the town succumbs to fear and suspicion, amplifying the threat. Amidst the spreading paranoia, will the detectives uncover Shounen Bat's identity, or succumb to the mounting dread themselves?