Ui Hirasawa
Jun and Ui Jun and Ui have been friends since primary school. They went to the same junior high school and spent a lot of time together. In their first year, Ui always tried to persuade Jun to join the Light Music Club with her sister, but Jun refused and instead joined the Jazz Club.

In their third year, after the old Light Music Club members had left for university, Jun and Ui together finally joined Azusa in building the new Light Music Club (Wakaba Girls) and recruiting other members.

Azusa Nakano
Jun and azusa Azusa is introduced to Jun by Ui. After that, they became good friends. In times when Jun needs Azusa's help, such as taking care of Jun's cat while she is out, Azusa is willing to help her (even though she had no idea how to take care of a cat).

Azusa and Ui also tried to persuade Jun to join the new Light Music Club. Looking at the condition of the Light Music Club that needs at least four members, Jun quits her previous club and willingly gets herself involved in the Wakaba Girls music club as the bassist.

Sumire Saitō
Jun and Sumire Jun first met Sumire when Sumire was planning to take the tea set from the music room (a task given by her master, Tsumugi Kotobuki). At first, Jun and the other girls thought that Sumire wanted to join the club, but by the end finally knew that it was a task given by Mugi. After Sumire joined the Light Music Club, she begins to serve tea (just like Mugi) to the other club members, which Jun tends to enjoy.