On October 11, IU appeared on KBS 2TV's 'Yoo Hee Yeol's Sketchbook' to promote her third album 'Modern Times.'

However, she was not the only guest!  Choi Baek Ho, who was one of the artists featured on her album, also made a surprise appearance.  IU explained that her father used to sing Choi Baek Ho's "Against Romance" a lot in the karaoke.  She said, "I thought the song was the most charismatic song in the world.  I also sang it often in concerts."

Choi Baek Ho revealed that he first met IU while backstage for the special 100th episode of 'Sketchbook.'  She approached him asking for his signature so she could give it to her father.

IU said she wanted to be a sunbae like Choi Baek Ho, who waited until she was done recording so they could have pleasant conversations.

Lastly, Choi Baek Ho said about IU, "This is only the start.  She is a talented person."

SEE ALSO: Veteran actress Go Doo Shim praises IU's acting skills

On 'Sketchbook,' IU also talked about how the host Yoo Hee Yeol was in her music video for 'The Red Shoes.'  In it, he wore red skinny pants that made all the female staff members fall for him so IU brought out those very same pants to give as a present to Yoo Hee Yeol.

Check out these video clips of her interview and performances from 'Yoo Hee Yeol's Sketchbook'!