The Shadows family, known for their black appearance and tendency to produce soot when agitated, are a group of noble individuals who reside in a massive mansion located far from other humans. When a Shadow child reaches adulthood, they receive a Living Doll as both caregiver and second half - the faces they might have had if not for their complexion. Emilico is an energetic newcomer to this role who serves a quiet master named Kate. Despite their differences in personality, Emilico strives to fulfill her duties. As she gains knowledge about her responsibilities and meets other Dolls and their respective masters, Emilico learns more about the purpose of her existence.
One rule that all Dolls must follow is not to worry about trivial matters. However, given Emilico's natural curiosity, it may be challenging for her to ignore the deep secrets held within the Shadows House.