- Kim Hye-yoon
- Â Eun Dan Oh 32 episodes, 2019
- Kim Ro-Woon
- Â Haru / ... 32 episodes, 2019
- Lee Jae-wook
- Â Baek Kyung 32 episodes, 2019
- Lee Na-eun
- Â Yeo Ju Da 32 episodes, 2019
- Kim Young-dae
- Â Oh Nam Ju 32 episodes, 2019
- Jung Geon-joo
- Â Lee Do-hwa 32 episodes, 2019
- Lee Tae-ri
- Â 'A4' / ... 32 episodes, 2019
- Kim Hyeon-mok
- Â Ahn Soo Cheol 32 episodes, 2019
- Kim Ji-in
- Â Shin Sae-mi 32 episodes, 2019
- Song Ji-woo
- Â Park Ae-ri 32 episodes, 2019
- Kim Tae-Jung
- Â Chae Yook In (Dan Oh's classmate) 32 episodes, 2019
- Yoon Jong-Bin
- Â Lee Yang-sam 32 episodes, 2019
- Han Myung-hwan
- Â Kang Chul-nam (Dan-oh's classmate) 32 episodes, 2019
- Shin Yong-ho
- Â Sin Ba-ram 32 episodes, 2019
- Eom Hyo-Seob
- Â Eun Moo Young 17 episodes, 2019
- Choi Jin-ho
- Â Baek Dae Sung 15 episodes, 2019
- Bae Hyun-Sung
- Â Baek Joon Hyun 9 episodes, 2019
- Ji Su-Won
- Â Cha Ji-hyeon 9 episodes, 2019
- Yoon Jong-hoon
- Â Lee Joo-hwa 8 episodes, 2019
- Lee Ye-hyun
- Â Kim Soo-hyang 5 episodes, 2019
- Kim Jae-hwa
- Â Art Class Teacher 4 episodes, 2019
- Yu Ha-bok
- Â Nam Joo's father (Ep.9-10) 2 episodes, 2019
- Kim Ji-Yu
- Â Eun Dan-oh (young) 2 episodes, 2019
- Kim Yi-rin
- Â Oh Hee-joo (Nam-joo's older brother) 1 episode, 2019
- Jung Dae-Ro
- Â Kim Yang Il unknown episodes
