The protagonist. A silver tabby kitten. 2 to 3 months old. Female. Small in body but full of curiosity and energy. Loves milk. Since she is still a kitten, she speaks with a unique lisp known as "Chi-speak." First person: Chi. After eating, she rolls onto her back and says "Pon-poko-ra~" (Tummy's full).

Full name: Yohei Yamada. The son of the Yamada family. Second-grade elementary student. Chi calls him "Yo-hey." He has a straightforward and kind personality and is often overwhelmed by Chi's rambunctious energy. They fight sometimes but are close friends. He might understand Chi's feelings better than anyone else. First person: I (soft, polite). Second person: Mommy, Daddy, Chi, Guest. Male.

Full name: Kento Yamada. The father of the Yamada family. Chi calls him "O-to-san." Because he is a designer, he often works from home. He is the reliable breadwinner of the family, but he has a soft spot for Chi. He makes albums of photos he takes of their daily life with Chi. First person: I (casual). Second person: Yohei, Chi, Guest, Miwa-san. Male.

Full name: Miwa Yamada. The mother of the Yamada family. Chi calls her "O-ka-san." A kind mother who is good at cooking. She is a bit easygoing, and might have been a bit of a space cadet when she was younger. Chi respects her because she brings home "prey" (groceries/food). Female. First person: I (polite). Second person: Kento-san, Yohei, Guest, Chi.

Chi's first friend. Chi calls him "Blackie" (Kuro-ino). The Yamada family calls him "Bear-cat" because Yohei said he looks like a brown bear. He looks scary at first glance but is actually a good guy. He teaches Chi how to live as a cat. The boss cat of the town where Chi lives. Male. First person: I (rough). Addresses: Chi, Kocchi, Ann, Terry.

A stray kitten living in a cardboard box in the park. A bit bossy, but actually a kind and shy character. After meeting Chi in front of the fountain, the two love playing together. He has sad memories associated with the word "home." Male. First person: I (rough, masculine). Second person: You (blunt; referring to Chi).

A kitten who is a new friend of Chi and Kocchi. Close with her older brother Terry; the two are always together. She has a kind and reliable personality, often acting as the big sister who stops the others when they get too mischievous. Female. First person: I (polite). Addresses: Chi, Kocchi, Big Brother (Terry).

Ann's older brother and a kitten friend of Chi and Kocchi. He tries to be kind to everyone, which sometimes makes him a bit indecisive, but he is reliable when it counts. He comes to the park for walks with his mother cat. Both he and Ann love their mother very much. Male. First person: I (soft). Addresses: Chi, Kocchi, Ann.

A goldfish that Juri gave to Yohei and Guest as a gift. Usually elegant and cute, but... when people aren't looking, it's a super goldfish that defeats enemies with power unimaginable for a fish.

A cousin the same age as Yohei and Guest. She lives in Hokkaido and occasionally visits the Yamada house. She seems rambunctious but is kind at heart. She loves animals. Female. First person: I (polite). Second person: Chi, Uncle (Dad), Aunt (Mom), Yohei, Guest