Yayoi, worn out by her husband's cheating habits—never returning home on weekends even after marriage—had poured all her affection onto her son, Kota. Growing up seeing his mother's lonely figure, Kota gradually began to sincerely think, "I'll take the place of such an unfaithful father!" When he voiced his strong determination to protect her, Yayoi was deeply moved, and soon found herself developing new feelings.