Mayonaka Heart Tune centers on Arisu Yamabuki, a high school student who once found comfort in the late-night voice of a radio host known only as Apollo. That brief encounter leaves him with a promise he never got to keep, and the mystery of Apollo's identity lingers long after the broadcast has ended.
When Arisu reaches his second year, that distant memory leads him to his school's broadcasting club, where he meets four girls who are each chasing a future shaped by their voices. As he keeps searching for Apollo, the club becomes a place where ambition, connection, and uncertainty overlap: every conversation carries what the characters can say out loud, and what they can only hint at.
Mayonaka Heart Tune uses late-night broadcasts, everyday school life, and the intimacy of hearing someone through static to build a coming-of-age romance with a touch of mystery. Between Arisu's search and the girls' own dreams, the series follows how one voice can cross the dark and how listening to others can help each of them discover who they want to become.