Recently, Ryota, the son of the family, has become Kokoro with Hashimoto at his part-time job and often brings him home. Ryota, who didn't have many friends until now, has opened up to Hashimoto, and his mother, Ayaka, feels very happy and relieved to see him doing so. Both father and son gradually become closer with Hashimoto, but Hashimoto's real target is his mother, Ayaka...