It's not an easy job being an actor but it does have its perks. For one thing, there are kiss scenes with attractive co-stars that have to be filmed, sometimes for hours.

Recently filming Gu Hye Sun's kiss scene with Ahn Ja Hyun for "Blood" lasted three hours. Shown on April 7, it was the first kiss scene in the drama's 16 episodes so they had to get it right.

Ahn Jae Hyun's vampire doctor character had no experience dating let alone kissing humans. So he was expected to be inexperienced at kissing. The actors joked around about doing a good job then followed the director's careful guidance on making the kiss scene look convincing. Three hours is a long time to kiss anyone so hopefully they felt comfortable while perfecting that kiss.

It's not the only k-drama kiss that took so long to film. Kim Jae Joong and Go Sung Hee kissed for three hours to capture a few minutes of romance onscreen when they filmed "Spy." And they were outside on a chilly day filming in the snow. Kim Jae Joong also once said that kissing Wang Ji Hye in "Protect The Boss" required more than 50 takes.

And it was not easy for Lee Min Ho and Park Shin Hye in "The Heirs"' The couple's kiss scene on the roof of the drama's high school also took three hours to film. It wasn't just a kiss scene but it indicated an important turning point in their relationship. So, it needed to be perfect.

And Lee Min Ho's real-life girlfriend also got some prolonged kissing experience on set. When miss A's Suzy Bae filmed "Big" with Gong Yoo, he kept missing his lines and laughing right after kissing her. After 20 different takes, he joked that he was tired and wanted to "get it over with" fast.

Looking perfect on screen does not mean the kiss scene did not take work. The perfect "snow kiss" scene between Ji Chang Wook and Park Min Young passed by in a few heart-fluttering minutes but the "Healer" actors spent almost two hours filming the actual scene. The crew filmed it from various angles to make the most of the snowy day setting.

On the other hand, sometimes actors are just too good at kissing for their own good. When Son Ye Jin filmed a kissing scene with her drama husband Ha Suk Jin for a scene in "Shark," it only required one take. The chemistry between the actors was so impressive that the director approved it on the first try.

Both Son Ye Jin and Ha Suk Jin laughed and said they were disappointed.