After missing the last train at a company party, new hire Chika crashes at a male coworker’s home while his wife is away at her parents’ house following an argument. Chika appears to fall asleep as soon as they arrive. He begins touching her, and when she shows no sign of waking, he loses control and penetrates her. Days later, Chika unexpectedly returns on his day off, uses “that night” to blackmail him, and starts playing her own wicked game.