Rinko Shirokane, a first-year student at Yotsuba Women's University, previously served as student council president at Hanasakigawa Girls' High School. She is the keyboardist for Roselia, joining as the band's final member, and experiences extreme shyness during live performances, which initially caused her significant apprehension.

Rinko handles costume design and creation for Roselia, sewing all the band's outfits herself. Her hobbies include reading and playing online games. It was through online gaming that she met her best friend and fellow Roselia drummer, Ako Udagawa, who affectionately calls her "Rin-rin".

She dislikes celery but enjoys drinking hot milk. Rinko possesses black hair and lilac eyes, stands 1.57 meters tall, and celebrates her birthday on October 17th, making her zodiac sign Libra.