Blue Birthday

Ye-rim Kim

Oh Ha Rin

Hong-Seok Yang

Ji Seo Jun

Lee Jung-jae

Detective

Min-Hyung Song

[Photo Shop owner]

Lee Sang-Jun

Cha Eun Seong

Moon Joo Won

Ji Seo Jun [Young]

Cheon Ji Won

[Hye Min's friend]

Jeong Ye Dam

Ji Hye Min [Young]

Kim So Yoon

Oh Ha Rin [Young]

Park So Jung

Do Soo Jin [Young]

Yoo Soo Bin

Senior at Seoyeon High School

Min Chae Yeon

Ha Rin's co-worker

Kim Gyeol-Yu

Do Soo Jin

Park Joo-Hyun

Kim Eui Young

Kim Yi-Seo

Ji Hye Min

Lee Dong-Joo

Kim Shin Woo

Yoo Su-bin

Senior at Seori Highschool