Ryūgan

was a ninja from Takumi Village.

Ultimate Weapon Arc
He, along with the rest of Four Celestial Symbols Men, abducted Gaara's student, Matsuri, to get access to Gaara. They planned to use the One-Tailed Shukaku inside of him in order to resurrect Seimei so they could seek revenge against the Five Great Shinobi Villages, who they felt did not appreciate their village.

Ryūgan ambushed Gaara and Kankurō which ended with Kankurō challenging him. Ryūgan had the advantage after he obliterated the Black Ant and proceeded to strike Kankurō, but he revealed that it was another of his puppets. After Ryūgan showed he still had the advantage, he again tried to kill Kankurō, but Kiba Inuzuka and Chōji Akimichi arrived in enough time to save him. After they had already messed up several attacks, Ryūgan became impatient, and proceeded to attack them all. However Kiba had already put a plan in action plan; he and Crow, disguised as Akamaru, would charge Ryūgan and divert him while Akamaru repaired the Black Ant so Kankurō could trap Ryūgan within it. Kankurō succeeded and then used the Black Secret Technique Machine One Shot, impaling Ryūgan several times. Ryūgan's Garian sword was later taken by Hōki.

Trivia

 * His name, meaning "Dragon Eyes" comes from Seiryū, the Azure Dragon of the East.