Mitsuyo Tsukada

A novelist receives a letter from a female university student named Kubo about strange sounds that emanate from a room in her apartment. They begin to investigate incidents involving former residents, and eventually discover the shocking truths lurking inside the building.

Yuichiro is a college student whose sister went missing 15 years ago. That traumatic event hangs over him like a pall as he wanders Japan's S&M clubs. But his younger brother claims to be able to sense their sister with his "antenna".