Shiho Ichimura, 18, is a member of Mystery Kiss driven by a childhood marked by poverty and bullying. Her ambition to achieve wealth, specifically to own a large house with an expansive bath, stems from these hardships; visiting hot springs provided her only private sanctuary growing up. Within the group, she serves as a backup dancer and singer, often forced to wear a mask during performances. She harbors deep insecurity about her role, feeling she lacks lead singer Rui Nikaido's charm or fellow dancer Yuki Mitsuya's talent.

Her manager, Fuyuki Yamamoto, exploits her perceived innocence and "sweet face" to involve her in "badger games" – romance scams targeting wealthy men, orchestrated by yakuza affiliates Haruhito Yano and Togo Sekiguchi. Following Yuki Mitsuya's death, Shiho assists Yamamoto and the yakuza in disposing of the body to protect the group's image. This act leads to a forced agreement surrendering half of Mystery Kiss's future earnings to the yakuza. Consequently, stricter mask usage is enforced for Shiho and replacement member Sakura Wadagaki to conceal their identities.

Shiho's scam activities include targeting Eiji Kakihana through a dating app. Aware of his fabricated wealthy persona, she manipulates him into a meeting enabling Yano's blackmail attempt. Her animal-like appearance results solely from protagonist Hiroshi Odokawa's visual agnosia, a psychological condition causing him to perceive humans as anthropomorphic animals; later resolution of this condition confirms her human form.