Tamiko Yomota serves as the mother figure in the Yomota family, defined by persistent dissatisfaction and a critical stance towards her husband Kinekuni and son Inumaru. Her demeanor undergoes a dramatic shift when confronted by Maroko, a visitor asserting she is Inumaru's granddaughter from the future. Tamiko vehemently rejects Maroko's identity and story, displaying immediate distrust. This skepticism intensifies into active resistance, ultimately leading Tamiko to depart the household as Maroko's presence and the ensuing familial chaos overwhelm her.

Following her exit, Tamiko aligns herself with detective Bannai Tatara. They jointly investigate Maroko's background, uncovering information that suggests a pattern of disruptive behavior affecting multiple families. Tamiko presents findings indicating Maroko might be orchestrating the Yomota family's disintegration through temporal manipulation. Despite her efforts to expose Maroko as a fraud, an unforeseen incident prompts the family to collectively accept Maroko's claims, undermining Tamiko's investigative conclusions.

Her interactions consistently underscore friction within the family structure. She frequently clashes with Kinekuni over his perceived laziness and irresponsibility, while also expressing frustration with Inumaru's behavior. The narrative juxtaposes her struggles against recurring segments detailing avian behavior, implicitly contrasting animal adherence to natural order with the Yomota family's dysfunction, exacerbated by Tamiko's rejection of Maroko and subsequent actions.