Kaji Ren is one of the main characters in the WIND BREAKER manga series. He is is a second-year student at Furin High School, as well as the second year Grade Captain and a member of the Vaisravana Unit. His character is generally quiet and he tends to allow his vice-captains to speak for him. He is easily annoyed, especially after finishing a lollipop, and reveals his agitation. Nevertheless, Kaji tries his best to be a dependable grade captain and acknowledges his weaknesses with the expectations that his vice-captains will support him.