Voiced by: Yoriko Nagata (Japanese)
Jun is Azusa's and Ui's classmate who often hangs out with the latter. Ui tries to get her to join the light music club but ultimately fails due to a strange visit to the club room. She instead plays a Yamaha Sbv500 bass in the jazz club and is one of Mio's admirers. However, she starts to regret not joining the light music club when she hears about all the activities they do and eventually joins the light music club at the end of the series. She has a pet cat.