OVAs bundled with the 17th, 19th, and 23rd tankoubon volumes of the Golden Kamuy manga.

An action comedy set in the solar system, about a row over Himawari, Shinnosuke's younger sister, between the Nohara family and aliens. Shinnosuke has a fight with Himawari, because she ate his crème caramel. Suddenly, two mysterious men appear and Shinnosuke signs an agreement to leave her with them. They abduct the Nohara family to the Planet Himawari by UFO. On the Planet Himawari, Sunday Goronesky the Great says Himawari needs to be the princess of the planet in order to save the Earth and the Planet Himawari from the fateful crisis.

(Source: Manabu Tsuribe)

Prism Stars are performers on the new popular ice show, Prism Show. They are superidols whose techniques, singing and fashion sense are a cut above all others. Aira and Rizumu are two Prism Stars whose goal is to become the best, the Prism Queen; however, the road to success is bumpy. (Source: AniDB)

Photon Earth is a young and gentle boy with superhuman strength and "Baka" (meaning "idiot" in Japanese) scribbled on his forehead (apparently by his troublemaking friend Aun Freya). One day, he finds himself engaged to the beautiful fugitive pilot Keyne Acqua after writing "baka" on her forehead. And that's the least of his worries as he must protect both Aun and Keyne from the evil Papacharino, who seeks to steal the secrets of "Aho" (another word for idiot) energy from Keyne's grandfather's ship. (Source: ANN)