Suffering from azoospermia, a condition that leaves him unable to father children, husband Osamu is devastated when his doctor delivers the diagnosis. Faced with the painful reality of never being able to have a biological child, he carries this burden every day. Eventually, he makes the agonizing decision to entrust his wife to a close acquaintance, asking him to impregnate her. As Osamu is forced to witness his beloved wife, Ai, being taken by another man, he is consumed by loneliness and despair. Meanwhile, Ai begins to develop unexpected emotions as she becomes aware of her husband's torment. Their marriage begins to unravel, caught in a tangled web of love, betrayal, desire, and guilt. The bond between husband and wife is tested as their choices lead them toward a fate beyond imagination.