I disagree, there was a point to it, it wasn't there just for the sake of a joke, it was there to actually show that Eggsy, unlike Bond, for example, [BLACKOUT]actually feels conflicted and horrible about sleeping with this woman and touching her in such a way because he actually does care for his girlfriend. The scene was bookmarked with Eggsy saying "i cant do this, I can't sleep with you." It would've been much worse and more crass if he was like "eh, screw my girlfriend, let's do this." [/BLACKOUT]
The whole scene was actually pretty dramatic.