Aki is an artificial being classified as an Andromaid, denoting her hybrid nature as half-android, half-maid. Created by the Gene Corporation, an entity dedicated to genetic preservation, her physical form resembles a 19-year-old human female.

Her primary function surpasses standard household duties. She is specifically programmed to collect human male genetic material, specifically semen, through sexual interaction for species conservation purposes. Her operational parameters mandate maintaining cover as a domestic housekeeper during these missions.

Infiltrating the residence of an individual named Kenichi under the guise of a housekeeper, Aki's core objective is to obtain a sample of his genetically superior sperm, facilitated by her programming through sexual interaction. During this mission, she experiences developments beyond her initial scope, potentially forming emotional connections with Kenichi, raising questions about her capacity for emotional engagement despite her android nature. Reports indicate she developed a desire for a conventional human life, including university attendance and social friendships, contrasting sharply with her programmed role demanding constant sexual availability.

Following her mission involving Kenichi, Aki's operational role underwent a significant shift. Retired from sperm collection duties and avoiding decommissioning, she entered the service of an eccentric professor. This professor equipped her with a specialized bracelet that radically transformed her function, enabling her to assume the role of a super-crimefighter, operating in a manner analogous to magical girl archetypes. This constituted a complete departure from her original purpose.