On the February 16 episode of the SBS variety show "No, But Seriously!," Lee Mi Joo talked about a shocking thing that happened between her and fellow singer Jo Hyun Ah in the past. Both were guests on the show, the story was about an ex-boyfriend who was supposedly cheating on both women, which shocked fans and viewers alike.

Lee Mi Joo said, "It was a long time ago. It was Christmas. I couldn't meet my boyfriend that day because I had something to do," which shows how normal things were before the shocking news.

The singer talked about how she found out about the betrayal the next day. "A friend called me and asked if I knew a certain person. I said he was my boyfriend. Then my friend told me that he had called an older unnie from the same group out on Christmas. She even said that the unnie still hadn't come home," Lee Mi Joo recounted, emphasizing the shock of the situation, AllKpop reported.

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She told him about the end of their relationship after talking to him. I called him, and he denied it to the very end. So I told him we should break up," Lee Mi Joo said, illustrating the emotional impact of the betrayal, per The Chosun Daily.

Lee Mi Joo stepped in to stop Jo Hyun Ah from getting involved with the same man, which changed the story again. Jo Hyun Ah confirmed the intervention by saying, "Mi Joo told me about him too," revealing the unexpected connection between the two singers.

Lee Mi Joo said why she told Jo Hyun Ah, "I already knew about him. She was talking about him so happily, and I said, 'Unnie, no.' Then I told her everything," she said, demonstrating her protective instincts.

She further criticized the man involved: "I told her he liked me, too. When he was telling Jo Hyun Ah he liked her, he was also saying he liked someone else. He was confessing to multiple people at the same time. He even cried and begged me to date him. He's really trash."

Viewers got to see the candid discussions about their busy lives behind the scenes of the stars' professional lives; in doing so, they were able to learn a lot about friendship, trust, and the challenges of having relationships in the K-Pop industry.