Twelve years ago, Narumii divorced her husband and raised her son Tatsuya all on her own. Having received his mother's full love and care, Tatsuya successfully landed a job, finally allowing Narumii to complete her role as a parent. Though relieved, she began to feel a quiet loneliness. Meanwhile, Tatsuya invited his mother on a trip for the weekend, planning to confess a feeling he'd long kept inside—a confession not just of filial love, but of romantic desire for her as a woman.