Ryuichi Sakuma

Lead singer of the popular band Nittle Grasper along with Tohma Seguchi and Noriko Ukai, and friend of Shuichi. He left the band three years ago to pursue a solo career in America but returned to Japan to reform Nittle Grasper. Shuichi is excited at the news of Nittle Grasper's reunion, but that now makes Ryuichi his rival. Ryuichi is kind and sometimes seems to have the mind of a five-year-old, until he starts singing; then he becomes a really cool, mature, vocal god. Other characters have noticed that Ryuichi and Shuichi are quite similar in their child-like manner. His best friend is a pink bunny named Kumagoro (Mr. Bear in the English version), which is from K-san, his old manager. It contains a tracking device, and is from the K brand stuffed animal line. Not much is known about his past.

The author, Maki Murakami, supposedly named Ryuichi Sakuma after famous Japanese music composer and actor "Ryuichi Sakamoto."