Kahi took charge of teaching the 'D' rank group on the April 14 broadcast. Among the trainees in 'D' rank was Kang Dong Ho, who used to be Kahi's labelmate at Pledis.

Unfortunately, Kang Dong Ho kept making mistakes during practice. Kahi couldn't help but criticize Kang Dong Ho, saying, "Dong Ho, why are you so slow?" Fellow NU'EST members who saw Kang Dong Ho's unsatisfactory performance, commented, "I hope he does well... It's unfortunate."

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Kang Dong Ho also depressingly commented, "It's not going well as I wanted. I'm feeling a lot of pressure. I'm intimidated."

However, Kahi strictly said, "There are a lot of trainees who have never even debuted. I hope he receives a positive motivation from them. But honestly, I'm disappointed."