During the day, female employees of the high school 3 trainees. At night, Seolhee lives as a karaoke helper. The girl longs for the 14-year-old Jae Wook, a senior teammate like an amusement park. Then one day, an unfortunate accident occurs on the rides where Seolhee and Jaewook worked together. Jae-wook is fired with all responsibility, and Seol-hee feels guilty because she thinks the cause of the accident is large. After that day, she goes to Jawook and tries to help anything. Jae-wook feels burdened by such a girl and dangerous desires in her.