An old mansion reduced to ruins, a haunting case of confinement shrouded in dark, oppressive air... Human relationships entangled by tragic fate begin to writhe like insects. Hisayo, once possessing immense wealth and power, stood unchallenged in her position. Her husband, Koichi, was an adopted son who could never defy her commands. Meanwhile, Izumi was the daughter of Hisayo's father's mistress, and Hisayo's father had left a will bequeathing his fortune to her. Hisayo harbored deep hatred toward Izumi. On top of this, Kawada Yoshio, Koichi's biological brother, appears, and the insane household gradually crumbles, spiraling toward destruction...