Kinosaki Mao lost his mother at an early age and has lived with only his father Hajime since high school. When Mao entered university his father suddenly disappeared, leaving a note telling him not to worry about him. Four years passed, Mao was already graduating, and he had already come to terms with his father's departure, but the loss of his mother gradually developed a "phobia" or "gynophobia" disorder in him... One day his father Hajime unexpectedly returns, and not alone. He brings a new wife, Arima Shiori, into the house. Mao immediately falls in love with her, subdued by her kindness and motherly affection. Gradually he grows close to her and their relationship takes a different turn after she learns his sad story...