Seo In Guk denied that he became arrogant after the success of 'Reply 1997'.

On The December 12th episode of 'Radio Star', the MCs teased guest Seo In Guk by stating, "Seo In Guk got really big all of a sudden. I keep hearing you're getting more snobby."

Yoo Se Yoon added, "The tone he greets me in became lower", and Kyuhyun also added, "After the last filming, we said we'd become friends. But I don't remember if we ever talked casually or not. But today, as soon as he saw me, he said, 'We're friends'."

Seo In Guk complained that was unfair and said, "I did it because I was happy to see you since we said we'd be friends the last time". Kyuhyun replied, "Were we that close?".