On November 13, KBS 2TV aired a new episode of 'Mamma Mia' featuring Seo In Guk as a guest along with Kim Bo Min, Park Eun Young, Lady Jane, and Kim Ji Min. 

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On this day, the singer-turned-actor was given the awkward task of ranking the participants of the show in response to the question, 'Who do you think will be tiring to live with'? He ranked Kim Hyun Sook as number ten, saying, "Honestly, she seemed wild in the beginning.  However, when I saw her do things like ad-libbing, I came to think she was quite all right."

He put Kim Hye Sun at number eight, saying, "Doesn't she always tell you everything about the future, like the weather?" He was asked what he liked about her looks, and he said, "Her lips are really pretty."

Seo In Guk then chose Lady Jane as the number one most likely person to be exhausting under the same roof.  He explained, "I feel like she would keep talking back to me sassily."

Lady Jane said, "Seo In Guk is not my style, either."

Seo In Guk said, "Just like this."