Kuro is a female black cat and pet to Kanako Urashima. Kuro digilantly follows around her owner.
Capable of flying, Kuro possesses uniquely large ears and is able to talk in the anime (it is unknown wether or not she can talk in the manga as the only instance in which she talked turned out to be Kanako playing around with throwing her voice). In the anime she offered conversation and advice to Kanako as she fretted over her longing to be with her stepbrother. Kuro's arrival is usually announced by the sound of the bell tied to her tail.
- Tama and Kuro can lift 50 kg.
- Kuro is strong enough to carry a human while flying for a short distance.
- Ken Akamatsu explained in his notes that Tama, Kuro, Shippu and Leon were inspired by the "Four Legendary Animals of Japanese Mythology"; Tama was inspired by Genbu, Kuro by Byakko, Shippu by Suzaku, and Leon by Seiryuu.
- "Kuro" means "black" in Japanese.
- In the anime, Kuro's voice actress is Yuki Matsuoka in the Japanese dub and Sandy Fox in the English dub.
- In a concept sketch, a drawing of Takkun from FLCL appears as one of the designs.