Cerberus (ケルベロス, Keruberosu?) is a fictional character in Clamp's manga and anime series Cardcaptor Sakura. His name is more commonly known in its romanized version, Kerberos, which is also often shortened to Kero-chan. He is voiced in his more common "hidden" form by Aya Hisakawa and Masaya Onosaka in his "true" form.
In the English adaptation Cardcaptors, he is known as Keroberos or Kero. He is voiced in the series by Matt Hill (borrowed form) and Richard Newman (true form), and in the second movie by Wendee Lee (borrowed form) and Dave Wittenberg (true form).
Kero also appears in the anime adaptation of Clamp's latest manga Tsubasa: Reservoir Chronicle.