Birthday: March 23
Eriol Hiiragizawa is the main antagonist in the latter part of the series, known as the Master of the Clow arc. As the reincarnation of Clow Reed, Eriol possesses both Clow's memories and all his magical abilities. He wields a magical staff similar to Clow Reed's, can command Clow's creations Yue and Cerberus, and has created his own guardians: Ruby Moon and Spinel Sun. After Sakura Kinomoto passed the Last Judgment and became the official master of the cards, Eriol moved from England to attend Tomoeda Elementary School.
At school, Eriol is portrayed as a quiet and mature boy but shows a playful side when he joins his classmate Takashi Yamazaki in spinning elaborate lies about the history of objects, places, and events. While Sakura sees him as a normal student, Syaoran Li remains suspicious. It is soon revealed that Yue and Cerberus can detect Eriol's magic signature as being identical to Clow's, leading Eriol to erase Yue's memory after an accidental encounter.
Eriol came to Japan to assist Sakura and compel her to use her own magical powers to transform the Clow Cards into Sakura Cards. This transformation was necessary because the cards draw their magic from their master, and without conversion, they were slowly losing power. Similarly, the guardian Yue was also weakening, forcing Sakura's brother to transfer all his magical energy to prevent Yue and his alter ego Yukito from dying.
Sakura remains unaware that Eriol is behind the magical disturbances until near the end of the series when he reveals himself. He puts the city to sleep and challenges Sakura to convert the last two cards, Dark and Light, which must be transformed together. After successfully completing this task, Eriol informs Sakura that she is now more powerful than Clow Reed and asks her to divide his magical power between himself and her father Fujitaka, the other reincarnation of Clow Reed, so that Eriol will no longer be the most powerful magician in the world. He then takes Sakura, Syaoran, Tomoyo, Yue, and Cerberus to his home to explain why he needed to give her a reason to transform the cards, as doing so without a need could have caused them to spiral out of control or drained Sakura's life force.
Eriol's true age is unknown, as he uses magic to halt his aging process, keeping him physically the same age as Sakura. He is romantically involved with Kaho Mizuki, whom he originally sent from England to help Sakura during the Final Judgment and who supports Sakura through letters in the second arc. At the end of the manga series, Kaho returns with Eriol to England, and in the second anime movie, they are shown together when Sakura calls for advice.
In the anime adaptation, Eriol is the sole reincarnation of Clow Reed, with elements from the manga regarding Fujitaka's relation to Clow and inheriting half of his powers omitted. The final explanation at Eriol's house occurs the day after the final battle rather than immediately after, and it happens because Sakura seeks him out instead of receiving an invitation.
