Kenta was born as the youngest of three brothers. From his mother Kiyoka's perspective, he seemed like a quiet child who didn't assert himself. One year in the spring, his two older brothers started living alone, and their father was transferred to a new job, so life changed rapidly, and Kenta and Kiyoka began living as a mother and son. Kiyoka feels a sense of loss when her lively house suddenly becomes quiet. Seeing his girlfriend's mother in such a state, Kenta felt sad.