Pure Love

Kim Ji-kwang

Ha So-yun

Jung Woo-chul

Ma Eun-hee

Go Da-bi

Jung Woo-sung Im Si-wan as young Woo-sung

Kim Sun-mi Han Seung-yeon as young Sun-mi

Choi Joon-young's cousin (ep 59)

Son Dae-ri

Young Jung-woo

Kang Soo-ji

Choi Joon-young

Young Soo-ji

Choi Min-soo G.O as young Min-soo

PE Student Teacher (Woo-sung's crush)

Barista

Jung Soon-jung

Young Woo-sung

Young Sun-mi

Ha Jung-woo Kim Sung-kyu as young Jung-woo

Ha Soo-bin (ep 7)

Student

Young Min-soo

Jung Soon-jung's sister