Bristlefrost is a thick-furred pale gray cat with greenish-blue eyes, neat ears, and long whiskers in the Warrior Cats books by Erin Hunter. She is born as Bristlekit, and at six moons old she is apprenticed to Rosepetal, her mentor, and then becomes Bristlepaw. She was a warrior under Bramblestar's leadership in the lake territories. She was a spy for The rebels. The book cursor with Warrior Cats Bristlefrost.