Shiroi Neko no Gakkou

White Cat School is a school attended by cats who are still white and who have the potential to join the "White Cat Knights," an organization made up entirely of white cats. Students who graduate without their fur becoming colored join the prestigious White Cat Knights, but those whose fur becomes colored have their dreams shattered and disappear without a trace... The students who attend this strict yet dream-filled school study hard every day, dreaming of one day becoming a member of the White Cat Knights. The protagonist, Col, is one of them, with his innocent, cheerful, and simple personality. However, when his best friend Leonis, who has sworn to become a knight with him, starts to get colored fur, will he begin to change...? (Source: Akita Shoten, translated)