One day, after being discovered in an abandoned house by a rescue team, Mori suddenly finds himself in a children's protection center. Here, he begins to learn a new way of life – one that includes grand care packages sent by a mysterious patron. But when his closest friend is reunited with her mother and leaves the center, Mori learns for the first time the existence of a mother for every child, and decides to embark on a journey to find his own. But what sort of obstacles wait along the way?