Yui Hirasawa - Personality: The ultimate airhead who marches to the beat of her own drum. Always relaxed, she loves fun things and anything cute. - Characteristics: When she focuses on one thing, she displays incredible power, but she forgets everything else in the process. Thinking about difficult things gives her a fever. - Address terms: Calls Ritsu "Ricchan," Mio "Mio-chan," Tsumugi "Mugi-chan," and Ui "Ui."

Mio Akiyama - Personality: Serious and incredibly shy. A scaredy-cat who hates scary stories, ghosts, and being the center of attention. - Characteristics: The rare voice of reason in the Light Music Club. Usually reliable, but turns bright red and hangs her head the moment she's praised or teased. - Address terms: Calls Yui "Yui," Ritsu "Ritsu," Tsumugi "Tsumugi," and Ui "Ui."

Ritsu Tainaka - Personality: Energetic, carefree, and a bit of a tomboy. The president of the Light Music Club. - Characteristics: Bad at detailed work and submitting paperwork, which often gets her scolded by Mio. A mood maker who fools around with Yui to liven up the club room. - Address terms: Calls Yui "Yui," Mio "Mio," Tsumugi "Mugi," and Ui "Ui."

Tsumugi Kotobuki - Personality: A gentle, soft-spoken rich girl who is always smiling. - Characteristics: Has a strong fascination with commoner culture (like fast food and cheap snacks). Rarely gets angry and loves watching everyone else's chaotic interactions. - Address terms: Calls Yui "Yui-chan," Ritsu "Ritsu-chan," Mio "Mio-chan," and Ui "Ui-chan."

Ui Hirasawa - Personality: Yui's younger sister by one year. Very reliable, polite, and loves her older sister (Yui) more than anything. - Characteristics: Perfectly handles everything from housework to cooking and baking. Taking care of Yui is her reason for living, and she supports her sister unconditionally. - Address terms: Calls Yui "Onee-chan," and the other club members "Ritsu-san," "Mio-san," and "Tsumugi-san."