Kim Ha-neul as Hyo-joo

Yoo In-young as Hae-young

Lee Won-keun as Jae-ha

Lee Hee-jun as Pyo Sang-woo

Gi Ju-bong as Jae-ha's father

Lee Ki-woo as Lee Jong-chan

Jeong Seok-yong as vice-principal

Hong Wan-pyo as head teacher

Oh Na-ra as Lesson teacher

Lee Kyung-young as Chairman

Kwak Dong-yeon as Yoo Jong-Ki