The official website for The Seven Knights of the Marronnier Kingdom has announced four additional cast members for the series, which premiered on NHK Educational on October 3. These additions represent the royal family of the Country of Long Nights, a location featured in the narrative starting with the fourth episode as characters Eleonora, Insomniac, and Johanne arrive for a diplomatic mission. Naomi Shindō will voice Queen Hyrokkin, joined by Atsushi Ono as the prince consort Rollo, Ai Kayano as the heir presumptive Birgitta, and Yurie Funato as Kastehelmi. The anime, directed by Kiyoko Sayama at J.C. Staff, is based on the manga by Nao Iwamoto and is currently available for streaming on Amazon Prime Video.