

By Dramabeans
Young Kang Ha-ram
Wang Yong-chun, a man with spider tattoo.
Jang Hyun-soo / Grim Reaper #416 (real form), a friend of Kim Joon who was killed in the Mujin Time Mart incident.
Man-soo's mother
Je Soo-dong / Grim Reaper #419
Na Gwang-gyun / Crazy Dog
Kang Ha-ram Ok Ye-rin as child Kang Ha-ram Choi Myung-bin as young Kang Ha-ram

Choi Soon-jung, Ha-ram's mother. Lee Si-won as young Choi Soon-jung
Oh Man-ho, Man-soo's half-brother.
Oh Sang-min, Man-ho's son.
Leo / Kim Woo-shik, a K-pop star Jeon Jin-seo as young Kim Woo-shik
Child Kang Ha-ram
Grim Reaper #444
Young Han Moo-gang
Yoon Soo-wan/ Kim Sun Young Song Soo-hyun as young Yoon Soo-wan/ Kim Sun Young
Han Moo-gang / Black (Grim Reaper #444) / Kim Joon Choi Seung-hoon as young Han Moo-gang
Young Choi Soon-jung
Grim Reaper #007
Oh Man-soo Lee Seung-woo as child Oh Man-soo Lee Geon-ha as young Oh Man-soo
Soo-jin
Clara