The title is a pun on the name of the magazine the series ran in, Mac Fan (a Macintosh magazine). Fuan means anxiety.

From xkazemg: Through music, they met each other; they knew they were soul mates to each other. But he was already engaged to the woman whom he sworn he would love for the rest of his life, and she a raising star in the music industry… eventually they parted their ways and decided not to see each other again. But 14 years later, and after the death of his wife, her life was about to change again, after his daughter showed up in her life…

Kanade Sakuraba had an affair with a married man without knowing he was married. She suffers from insomnia due to a psychological trauma, but recovers from it when she hears the voice of the distributor whom she learned about while she was on a leave of absence. On the day she returns to work, she is introduced to her new boss, Yoshimasa Kohrogi.