Here are translated comments from Korean netizens:
1. Ah, so funny ㅋㅋㅋㅋㅋㅋㅋㅋ I can feel the sincerity.
2. So savage ㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋ
3. Yook Sung-jae's vocal version sounds so good ㅜㅜ
4. He did it so well ㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋ
5. Insane ㅋㅋㅋㅋㅋㅋㅋㅋㅋ
6. Wow, seriously! So funny.
7. Pointing at the company logo and saying goodbye.. Seriously ㅋㅋㅋㅋㅋㅋㅋ
8. Ah, crazy ㅋㅋㅋㅋㅋㅋ Let's have more of this series, as former Cube employees.
9. He really sings well.
10. Is he crazy? ㅋㄱㅋㅋㅋㅋㄱㄱㄱ
11. Wow, I didn't know he sang this well ㅋㅋㅋ I knew he was a singer, but this is my first time seeing him act.
12. Soyeon isn't even there, but he's doing the challenge at Cube with a standee, so funny ㅋㅋㅋㅋ
13. Yook Sung-jae sang a short part on a variety show before, and it sounded amazing... What was it, anyway, he sings really well, it's incredible.
14. So funny ㅋㅋㅋㅋㅋㅋㅋㅋ They must have a good relationship to film it like this ㅋㅋㅋㅋㅋ Going there himself to film it is the real deal ㅋㅋㅋㅋㅋ
15. No, he's really crazy ㅋㅋㅋㅋㅋㅋㅋㅋㅋ
16. Like a madman ㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋ And he sings incredibly well too ㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋ
17. Such madness, to actually visit the company he 'quit' to film ㅋㅋㅋㅋ
18. Goodbye~ Is the next line '18 youth'? ㅋㅋㅋㅋㅋㅋㅋ I'm dying of laughter ㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋ
19. ㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋ Ah, that's genuine emotion.
20. Sung-jae's song is so good ㅋㅋㅋ What a great vocal tone.
21. ㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋ This concept is amazing.
22. ㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋ This is what a true 'quitter' looks like.
23. Soyeon isn't even there, but he filmed this challenge himself and uploaded it to (G)I-DLE's official account, so funny ㅋㅋㅋㅋㅋㅋㅋㅋ
24. What happened to Yook Sung-jae?? ㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋ
25. The real 'quitter' has arrived, so funny ㅋㅋㅋㅋㅋㅋㅋㅋ
26. And he sings incredibly well, and he's so handsome.
27. No, he did it too well, handsome and funny, ah.
28. ㅋㅋㅋㅋㅋㅋ Why is Yook Sung-jae so funny?
29. The 'quitter' has truly arrived ㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋㅋ
30. I thought he filmed it alone without Jeon So-yeon, but it wasn't like that after all ㅋㅋㅋㅋㅋㅋㅋㅋㅋ
31. He's a real 'quitter' ㅋㅋㅋㅋㅋ
32. So funny, hope this goes viral.
33. The 'quitter' ㅋㅋㅋㅋㅋㅋ It sounds good when a man sings it too.
34. Yook Sung-jae sings well, as expected.
35. Crazy idol ㅋㅋㅋㅋㅋㅋ
