Suntong shim

Appearing in s1, ep.31. 20yrs old. He was sentenced to 4 years and 6 months in prison for assault.

When Jiwung rebels, he curses and threatens him along with Dongsu. After Gyeom beats Jiwung, then, along with Dongsu and Gyeom, they harasses Jiwung's gang and beats them mercilessly with a plastic bottle filled with water for example. Looking at Na Hwa-jin's comment when she was talking about prison inmates, it seems like she was a problem child like Kim Hak-jae even before her incarceration.

In the epilogue, he greets Jiwung as he came back again.