During the airing, a fan asked, "Tell us a secret about your members," to which Seunghyun revealed, "Hongki got butt surgery." 

Hongki then explained, "I got it twice," while Jaejin added, "That's why we gave him the nickname Hongki-jongki ('jongki' refers to the boil on the skin)." 

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Hongki continued, "Thats why I have a lot of scars [on my butt]. I am insecure about my butt. The reason why I can say this [on air] is because my fans know this. In China when I was holding a solo fan meeting, the boil got so big that I couldn't sit, stand, walk, or anything. So my fans asked what was wrong, and I told them bluntly that my butt was hurting." 

Meanwhile, prior to talking about Hongki's insecurity, Jonghun put fellow member Jaejin on blast and revealed that Jaejin makes frequent visits to get his body hair waxed.