C

is a Kumogakure jonin who escorts the Raikage to the Kage Summit along with Darui.

Five Kage Summit arc
He and Darui were called to escort the Raikage to the Five Kage Summit in the Land of Iron. When the Raikage jumped through a window, he suggested to Darui that they follow him, but Darui said that he would use the door. After that, he was showed to be the one who noticed that Team Samui had been followed.

During the Kage meeting, he quickly jumped to protect the Raikage after he smashed the table, because the bodyguards of the other Kage entered into defensive position. After the other bodyguards returned to ther respective place, Shī and Darui did the same. When White Zetsu appears during the Five Kage Summit, Shī along with Darui guard the Raikage and follow him to the battle with Sasuke Uchiha.

Abilities
Shī seems to have a keen sense of detection, as demonstrated that he noticed that Team Samui had been followed by Naruto Uzumaki, Kakashi Hatake and Yamato. Also, he could sense a lot of chakras disappearing when Sasuke Uchiha fought against the samurai, and was able to tell the Raikage and Darui that Sasuke was below them. He is also proficient with genjutsu.

Trivia

 * Shī is the Japanese pronunciation of the letter "C". This parallels Jei's name, which is the pronunciation of the letter "J", and Killer Bee's name, as "bī", the Japanese pronunciation of "bee", is also the Japanese pronunciation of the letter "B".