One day however, she is found by Kyutaro Horikita, an unfriendly second-year student with a talent for cleaning, and is drawn into a mysterious door in the room through her classmate and delinquent Sakaguchi's voice calling for help.

The school's chairman and Kyutaro's brother-in-law, Koichi Kitagawa, recognises Fumi's talent and decides to invite her as part of their family, explaining the situation to her.

The Horikita family are "Sweepers", people who enter the mind vaults of others to cleanse their souls of bug infestations that are the result of uncontrollable negative emotions.

As Fumi undergoes training to become a Sweeper and Kyutaro's partner, she stumbles upon an extraordinary power lying dormant inside her: the "Queen", a rare existence that can allow the bearer to have mind control over others.

She wrote that the while series "doesn't do a whole lot to distinguish itself or give us any major surprises, it is still a very enjoyable read filled with the humor and small romantic elements that Motomi does so well".