Once a promising and celebrated talent, Yosuke Nakajima turns 40 this year. However, toyed by fate's cruel twists, he gave up on his dreams and returned to his family home. What troubled him even more was the reality that his biological mother had divorced, and his father had remarried a new woman. His father paid little attention to his son, spending each night with his new wife, Mitsuko—something that deeply pained Yosuke. For him, it became only natural to see Mitsuko not merely as a mother figure, but as a woman.