Lee Hyun Woo is Jealous of Yoo Seung Ho?

The two actors from 2010 KBS drama Master of Study, Lee Hyun Woo and Yoo Seung Ho have since been close friends since that time. So why is Hyun Woo jealous of his friend?
Yoo Seung Ho recently enlisted in secret to the army in March.

Lee Hyun Woo said, "Seung Ho is talented, so he was able to find a place for himself as an actor relatively fast. I′ve just gotten my name out there."

"It′s usual for men of our age to enlist, but for us (celebrities), it seems really early," he said. "I′m jealous of how he left after achieving so many things, but I want to continue to act for a while."

Lee Hyun Woo appears in Be Covert, Be Great, the record breaker film that has so far gathered a four million audience, as a North Korean spy disguised as a South Korean high school student.