In 2012, Sumikko Gurashi made their debut as characters with slightly negative traits who prefer to stay in the corner of a room. This group of characters includes "Shirokuma," a polar bear that is sensitive to cold, "Penguin?" (with a question mark in its name), a penguin that is uncertain about its own identity, "Tonkatsu," an uneaten piece of pork cutlet, "Neko," a timid cat, and "Tokage," the last surviving dinosaur who conceals his true nature. The success of the franchise has led to the creation of various products such as toys, books, stationery materials, video games, and most recently, a feature film.