Chiaki serves as one of the three maids working for the Hadou Financial Group under Ruri Hadou. Her primary duties involve managing Ruri's personal affairs and providing operational support during emergencies. She works alongside fellow maids Makoto and Sonia from an underground command center, where the team coordinates repairs and logistical assistance for the mechanized unit Demonbane during its combat operations against the Black Lodge. Among the three maids, Chiaki uniquely serves a dual role as both an operator and a mechanic responsible for repairing and maintaining the Demonbane unit.

Chiaki is recognizable by her brown hair styled in a ponytail with distinctive cheek curls, spiky bangs, and a ribbon hair tie. She consistently wears a standard maid uniform complete with a headdress, fingerless gloves, and ribbon accents, and is always accessorized with glasses. She speaks with a Kansai dialect and uses the first-person pronoun uchi, presenting herself as a bright and cheerful individual. Her role is consistently operational and supportive throughout the series. During investigative work into supernatural disturbances, such as the events at Innsmouth, Chiaki contributes valuable situational observations, including identifying physical traits indicative of Deep One hybrids. She serves as the leader of the three maids, and when both Ruri and Winfield leave the command center, command authority is entrusted to her. Chiaki also provides explanations of Demonbane's armaments and weaponry, reflecting her technical expertise as a mechanic.