Retsuko's mother is based off a Red Panda. Much like Retsuko, and her own mother that appeared in the shorts, she has orange fur that has dulled with age, black eyes, brown "tear stains", a white stripe next to the tear stain, and a white muzzle, ears, and eyebrows. She has brown legs and hands that are the same color as the tear stains, and a striped tail.

(Source: Aggressive Retsuko Wiki)