Tomiko Tominozawa operates as a Tokyo art dealer with distinctive blonde hair and lilac eyes. In Episode 5, she personally delivers an art exhibition invitation to Kana Hoshisato, coinciding with emerging rumors of a bear-like monster at Yumemi Hoshisato's school that spur Kana and Makoto to investigate. During Episode 6, Mariah Grene directs Kana to steal a specific Artifact from Tominozawa's museum as payment for facilitating Maeve Hoshisato's return. This mission requires Kana to adopt her Phantom Thief Hatena identity and infiltrate the establishment to secure the Artifact.