Ririchiyo Shirakiin is the well-protected daughter of a prominent family. Ririchiyo has spent her entire life as a sheltered and dependent girl due to her diminutive build and wealthy background, but she has determined to alter all of that. However, there is one problem: the little girl has an uncontrollable sharp tongue and poor communication skills. Ririchiyo moves in with the help of a childhood friend to Maison de Ayakashi, a hidden high-security apartment complex that, as the unsociable 15-year-old quickly finds, is home to a slew of strange people. Furthermore, their eccentric personalities aren't the only odd thing about them: each occupant of the Maison de Ayakashi, including Ririchiyo, is half-human, half-youkai.