Oh how wrong I was.
PEACH HEAVEN (Momoiro Heaven!), by Mari Yoshino. First published in 2007 and first published in North America in 2017.
PLOT:
Ever since her father died, Momoko Shino has had to help support her family by taking up her father's penname and writing erotic romance novels in his stead. None of her classmates have any idea that "George Aihara" is just unassuming (if somewhat exhausted) girl...that is, until she stumbles upon class idol Ranmaru Inui having sex with their English teacher. She uses the encounter for her next book and Ranmaru finds out her secret. He eventually agrees to keep it on one condition: that Momoka become his slave. After all, how can a teenage girl who has never so much as kissed a boy write good erotica unless someone teaches her the ways of romance?
