Clef is the chief of all sorcerers in Cephiro, and was formerly Princess Emeraude's attendant. In the anime, he is turned to stone by Zagato shortly after being introduced to the three girls in the first episode, although he fights the spell and communicated with them through Mokona. In the manga he is referred to as Guru Clef and is not turned to stone. He also leads all of Cephiro until a new pillar can be found. He and all other magicians used their willpower to create a castle to hold the inhabitants of Cephiro.

In the manga Clef is often seen with Presea, who does not die and has romantic feelings for him. In the anime he is both loved by Sierra and the deceased Presea. When he first meet the girls, he reacts very unpleasantly to Umi and Fuu's calling him "squirt".

His name is derived from the Mazda Clef.

Voiced by Steve Staley and Nozomu Sasaki.

Source: Wikipedia