Our protagonist, Arata Hibino had always loved his mother, Manami when he was little. Seeming as though to leave his mother who cannot let go of her dead husband, he decided to move out and live by himself.

One day, he accidentally injured his hand. Having heard what happened, his mother became worried and decided to stay with him until he was fully healed.
Cooking food for him, helping him change—Manami gained back her former role as a mother and looked after him.

Taking baths with her son however, also became part of her role as a mother......

[Translated from ANIM Official Website]