The Owner and Butler of the Abandoned Mint Garden.

Jougasaki Nanaki, an escapee from a special child development center, survives on the streets by stealing. A chance encounter with someone from his past leads him to a large, run-down mansion on the outskirts of town. There, he witnesses a small boy disappear through a wall right before his eyes.

Intrigued by the boy's secret, Jougasaki decides to stay and become the household's butler. But the mysterious boy, known only as "Bo-chan," has plans of his own for the curious thief.