Kimiko Dewa operates a Kyoto pharmacy specializing in insect-exterminating robot dolls, including the Hoihoi-san line. Initially drawn by her love for dolls and finding Hoihoi-san cute, she purchased one, only to become horrified witnessing its violent capabilities overnight. This experience instilled a lasting aversion to the robot's core function, despite her ongoing role selling them.

Seeking a non-violent companion, she later acquired a Combat-san unit from a rival company. Kimiko crafted a dress for it and issued explicit commands against extermination. The robot disregarded these instructions, persisting in killing pests while delivering verbal combat reports. Disillusioned, she sold the Combat-san to Aburatsubo-kun, a regular pharmacy customer.

Her interactions with Aburatsubo-kun reveal his mostly one-sided romantic interest, which Kimiko does not reciprocate due to his obsessive spending on robot accessories and upgrades. This dynamic underscores her pragmatic view of the robots as products, contrasting with her initial fascination. Her friendship with Mutsumi "Mu-chan" Fushikawa offers occasional context for her experiences.

Throughout, Kimiko Dewa functions as a retail employee navigating the stark contrast between the robots' cute aesthetics and their brutal functionality. Her attempts to humanize or pacify the combat dolls reflect an enduring internal conflict between her appreciation for doll collecting and her discomfort with their designed purpose.