Is Kissing Sensual Only Because We Make It So?

I was thinking, kissing,is a sensual act one does to indicate their love for someone else, whether it be a family member, lover, or pet. But what made kissing be that sensual? I guess since humans are very much into touching one another in order to display feelings, it is natural kissing would follow. But how did kissing come about?

Was it because when two people are making love (traditional style, mind you) that it is something to do to avoid talking, or just because it is convenient. I mean, it (kissing) only feels good because in society today that's what we are told and that's what we know. Why isn't licking someone's chin the same as kissing, because of society? Maybe. Sure you can argue that it is fun and feels good, but there was definite societal influence.

If you were to take 2 children, and never have them exposed to society, put on an island and were brought up, by seperate 'parents', and manage to have them develop feelings for each other, all the while, never teaching them about intimacies as we know, would they instinctually kiss? Or could you 'train' them that licking a chin is a sensual sign of affection?

I think it's possible, but I also feel like thousands of years of human evolution has somehow ingrained 'kissing' into humans, so that it happens naturally.