Kokin, also known as Kokin-chan or Coreen in the English dub, appears in the film *Soreike! Anpanman: Kirameke! Ice no Kuni no Vanilla-hime*. The character meets Princess Vanilla after the princess flees her palace due to her inability to create ice cream. Kokin travels alongside Princess Vanilla and Anpanman, during which the princess discovers the reason behind her struggle. Their bond is highlighted by a soundtrack track titled "Vanilla Hime to Kokin no Yuujou" (Princess Vanilla and Kokin's Friendship). Kokin has no documented presence in other seasons, movies, OVAs, or spin-offs, and no details exist about the character's background, personality, design, or development outside this film.