Seiji was born as the second son of three brothers. His mother, Reika, had the impression that he was a difficult child to deal with, but... One spring, his older brother got a job and lived alone, and his younger brother enrolled in a boarding school. Seiji and Reika's life changed rapidly as their father moved away from home, and Seiji and Reika began to live as a mother and son. The once lively house suddenly becomes quiet, and Reika feels a sense of loss. The state of her mother