She and Krystal were guests on 'Radio Star', along with Defconn and Kim Kyung Min. During the recording, Kim Kyung Min kept making offhand remarks, burping out of nowhere and asking, "When you go throw out food waste, do you wear the same thing you're wearing now?".

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Sulli, ever so polite, responded to his random question and said, "We don't have to throw away food waste because we live in an apartment." Kim Gu Ra applauded her efforts and said, "You're working hard", and then added a joke to say, "Just think of it as the punishment for your 'Running Man' mistake from before."