Myself and my Korean friend watched a hot Korean movie.   The sex scenes are near explicit and the fucking action in missionary looks real.    The guys really pump it although simulated.   My friend says most Korean hot movies are like that.  I can say they put the tame American soft core movies to shame.   If you have noticed, the girl never stays underneath the guy for more than 20 to 30 seconds and she is in top simulating CG which is boring.