Kero-chan

Cerberus, also called Kerberos or simply Kero, is the guardian of the sun who protects the Clow Book.

Initially, Kero is presented as a lion cub, or rather a stuffed animal or plush toy with orange-yellow fur, large ears, and small white wings.

However, its true form is that of an enormous lion or tawny puma without a mane, with huge white and angelic wings, and a metal breastplate and helmet, encrusted with a large red gemstone.

Kero is bossy and demanding, but secretly he cares a lot and has a clear sense of direction.
Kero's hobbies include playing video games and eating snacks and sweets (he loves sweets more than almost anything else), although, since he gets his power from the sun, he generates his own energy and doesn't need to eat to survive. He has a particular fondness for cakes, cookies, and chocolates. He doesn't seem to understand the concept of sharing.

Although he has been a willing servant all his life, Cerberus can be somewhat egotistical, obsessed with his "genius," and is seen bragging about himself after watching most of Tomoyo's recordings.

Despite his sometimes erratic behavior, Cerberus is extraordinarily intelligent. He possesses extensive knowledge not only of the Clow Cards but also of all kinds of mysticism, and has a special ability to read magical auras. He is often not as naive as he appears.
Cerberus doesn't like to dwell on the sad and depressing aspects of life, which possibly explains why he turns to so many pleasurable pastimes, such as food and video games, to distract himself from them. However, this doesn't mean he's immune to these realities.

He has a strange Osakeño dialect.

Kerberos was created by the Magician Clow long ago (the exact date is unknown) to represent the Sun and be one of the guardians of the Clow Cards. Upon Clow's death, he sealed Kerberos on the cover of the Book of Clow, giving him the mission of protecting the book's seal and choosing the new master of the cards once they had all been captured. At the same time, Clow altered the memories of Kerberos and Yue so that they would not remember many of Clow's distinguishing features, such as where they lived, and so that they would believe they had witnessed his death.