Define flower boy:

A commonly used term in South Korea since the mid-2000s that refers to young men with a great sense of personal style and fashion, popularised by pop idols, who may seem effeminate, in part because they are often shown with make-up, such as eye-liner or lip gloss. Another cause may be that, as most of them are in their late teens to early twenties, they look rather boyish.

Lee Taemin is in his final year of high school but has found himself in a bit of a predicament. Not only does he have to live the rest of the year as a girl, he got you, an apathetic introvert, as his roommate. His only saving grace is that Baekseok Girls' Grammar School has an intense music and dance program that fulfills his desire to become an entertainer. 

Jung Eunji is your childhood friend and lives in the dorm across the hall from you. Although also in the music and dance program, she is somewhat shunned amongst her classmates for being the class clown and not taking her studies seriously. However, you know how hardworking she is. Things get messy when you find out her boyfriend and Taemin know each other.

Son Naeun is arguably the most popular girl in school. She is Eunji's roommate and is enrolled in Baekseok's athletic program. The contrast between her sweet appearance and fierce passion for sport makes her a common target of affections from boys in neighbouring schools but she has yet to get a boyfriend. That starts to change once Taemin arrives.

Shim Changmin is a student at a nearby university who also acts as student teacher for some of the classes in the music and dance program. He primarily composes music and writes lyrics for Baekseok to use under various circumstances. In his spare time, he enjoys photographing nature, and his good looks often attract the attention of the girls at school.