EXO recently made an appearance on the hit variety show “Knowing Brothers” as six members to promote their most recent hit comeback.

During a segment of the show, guests take a turn trying to get the rest of the cast to guess what they meant by a certain sentence, Chen’s turn was up and he confessed that he hated getting this done.

The MCs took turns trying to guess, eventually, Heechul guessed it correctly; he guessed that he had gotten his lingual frenulum cut. Lingual frenulum is a fold of mucous membrane that’s located under the center portion of your tongue, you can see it if you raise your tongue looking in the mirror.

Chen explained,

“When I was young, I thought my pronunciation was hard, so I guess I was feeling it. I went to do that procedure, so surgery is scary. I asked him (the doctor) ‘what kind of surgery is that?’ he said people do it on their lunch breaks at work and leave.

They said I didn’t have to worry about it. But after the surgery was done, I felt extreme pain after the anesthesia wore off.

The pain of biting on my tongue continued for three days. My tongue kept swelling as time went by, I couldn’t eat properly. I couldn’t even swallow saliva, so I went to the hospital again; I took medicine and got better.”

He says he regrets it because he later found out that it doesn’t affect singing much.

Related: EXO Kai Threatens To Call The Police On Sasaengs Lurking Outside His Dorm

What do you think of Chen’s singing?