 His first acting role was in the second season of teen drama "Sharp" in 2005, where he played Baek Jin-Woo, co-starring labelmates Go Ara and Kibum.At that time, he gained popularity among female student fans due his unique appearance that made him seem like he popped out of a genuine manga.That same year, he appeared as an extra in the KBS2 TV series "Loveholic" and was a regular MC for the cable music show "".