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During the recording of their housewarming party on the upcoming episode, Heechul would accidentally call his wife, "Sulli yah", which raised the eyebrows of his celebrity guests who asked Guo Xue Fu, "Does your husband usually call you, Sulli?". She responded, "Since the beginning, he would frequently call me that."

Heechul shared during his interview, "That was something I wasn't even aware of. I didn't realize that I would call Sul Bu (Xue Fu) the wrong name at times until now, but it turns out Sul Bu remembers it all. I am a bad guy. I am so sorry."

Guo Xue Fu shared, "Everything else is fine but how could he get my name wrong... I think this is something I should be angry about. Oppa is definitely a 'bad boy'."

Can Heechul and Guo Xue Fu work this out? Catch the episode today at 10 PM KST!