Tanaka presides over the tennis club frequented by the protagonist, his sharp pragmatism immediately roused when an android mirroring a fellow member emerges as the protagonist’s sister. Disturbed by her abrupt presence and absence from prior conversations, he methodically dissects discrepancies in the protagonist’s account, weaving doubt through club interactions. His insistence on probing the android’s origins and demanding coherent answers amplifies friction between concealed truth and external observation, framing the struggle to safeguard secrets against his relentless scrutiny. Though his inquiries anchor tension around the android’s legitimacy, his own history, motivations, and personal connections remain unexplored beyond the original narrative’s brief scope.