Sex Is Zero 2(2007)

Original title: 색즉시공 시즌 2

In his 10th year at college, Eun-sik is part of a nearly ideal campus couple with swimming champ Kyung-ah. While their three-year relationship is solid, Eun-sik struggles to get to the next level with Kyung-ah; despite the help and support of his friends, he can't manage to get her into bed.