While her husband is away on a business trip, Misaki (Akasaka Runa) is caught cheating by her son, and from that moment, she becomes his plaything—used and dominated as if her body were nothing more than a toy. Though initially resistant, Misaki gradually succumbs to pleasures she has never experienced with her husband, her heart overtaken by forbidden ecstasy. Immersed in this new sensation, she realizes upon her husband's return that his touch can no longer satisfy her. Tormented by this truth, she silently bears her anguish, holding back tears alone in the dark.