One fateful day, Su-jin asks her college roommate Ji-yeon to fill in for her for a shift at her hostessing job at Salon,
a karaoke box in Seoul. 
Ji-yeon sees the job as an alluring new way to save up for her dream trip to Hawaii and becomes increasingly involved in Salon, unaware she is going down a dark trajectory. 
Meanwhile, Su-jin becomes closely acquainted with Ji-yeon's boyfriend at school.