Koharu Nanakura is a student at Four Star Academy, where she is an administrator of the Moon Beauty Class and serves as student council president. She was formerly enrolled at Venus Ark before returning to Four Star Academy after graduation. As a second-year middle school student, Koharu is known for her gentle, quiet, and delicate nature, though she remains hopeful and does her best to support others. She became an idol after being inspired by the elegance of Yozora Kasumi, whom she met when Yozora helped her after her glasses fell off; this encounter led Koharu to audition for the Moon Beauty Class. Koharu has been close friends with Yume Nijino since elementary school, and the two applied to Four Star Academy together, sharing a dormitory room despite being in different classes. Through Yume, she also became close friends with Laura Sakuraba and quickly bonded with Mahiru Kasumi. In the film Aikatsu Stars! Hoshiboshi no Progress, Koharu appears as a supporting character. She is a sexy-type idol whose preferred brand is Romance Kiss. Her natural shyness and healing presence allow her to get along with a wide range of people, and she is admired for her reliable and responsible role as student council president.