Yinlin Chou is a Practitioner of Baguazhang and the female of the Santoryu.
Yinlin is a fair-skinned young girl of average size. Yinlin tends to wear chinese dresses, even at times appearing rather skimpy, that draw attention to her breasts and legs. They even tend to be rather skimpy, suggesting she doesn't have much modesty.
She care about her teammates, looking out for them.
She starts of the battle with the Ryozanpaku team during the DofD tournament, quickly tracing circles around Kenichi Shirahama and Miu Furinji. After Yo is defeated, she duels with Miu. She is defeated when Kaku Shin Ten throws his fan at her and causes her to be hit by Miu's punch.
She is currently on the run with Kaku and Yo from the Black Tiger White Dragon Alliance and is being sheltered by the Ma family. While riding a train with her teammates, she is unable to defend herself as effectively against the assassins sent after the three due to the narrow confines of the train. After Kei Retsumin is defeated by Apachai Hopachai, Chou works with Kaku and Yo as minimum wage workers to repair the restaurant and to save their lives.