Ginji, living alone in Tokyo on a work assignment while his wife and son remain back home, endures his loneliness in a cheap lodging. One day, a young couple moves in next door. Drawn to Kana, the pure and innocent young wife who exudes no trace of worldly weariness, Ginji finds his heart stirred by her presence, the fatigue of daily life instantly vanishing. Unconsciously, he begins spying on her routine, reaching across balconies to touch her laundry, becoming increasingly obsessed with her daily life. Unaware of Ginji's growing fixation, Kana visits his place one day. Overcome with desire, Ginji pulls her into his arms, and the two begin a forbidden affair.