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Park Bom started the conversation about the things she finds funny and mentioned that she likes Yoo Jae Suk's style of jokes. At this, Song Ga Yeon shared, "I like [Shin] Dong Yup a lot these days", which left Lee So Ra noticeably uncomfortable for a sudden second (the model and Shin Dong Yup had dated for five years before breaking up in 2002).

Lee So Ra looked with surprise over at Bom and remarked, "What is she saying", as she and Bom started to crack up at the awkward situation. Bom hilariously started to apologize on behalf of Song Ga Yeon, stating, "Unni, it's because she's young! I'm Sorry! I'm Sorry!", while Song Ga Yeon looked on confused.

The clip ended with the first rule of living with a group of people: "Learn info about each other beforehand!"

Check out the hilarious clip above as you await for 'Roommate's premiere on May 4 at 4:20 PM KST!

[Thanks to everyone who sent this in!]