Gold Miss Lee Gaon made a successful career as a personal trainer and is in a rival-like relationship against the famous romance novelist, Jiho, famous for his notorious badmouthing.

* Gold Miss in South Korea is an unmarried woman with high socioeconomic status and level of education.

Gaon went to her frenemy Sera wedding ceremony and somehow ended up helping her escape. And her groom? It was Jiho, the man who slung towards her mouthfuls of criticisms and insults one after another.

They realize they were from the same highschool class...

While Jiho was on his way to meet Gaon, the two were transported twelve years into the past...

"That soft boy was that badass delinquent in highschool?! And he liked me as well?!