Well, being as you're pictured with a dog - I'll start there. Dog kisses are notoriously generous in nature. There is also generally an overabundance of saliva and drool. While some consider this pleasant, I have a bit of trouble forgetting what the tongue that is licking my face, was licking very recently ... as they sat with their legs spread out most indelicately.

As for human to human - at the very least, one ideally will feel pleasurable tingles, and perhaps the urge to prolong the contact - or not.
To the other extreme, as the heat rises, and kissing intensifies, one may gradually wish to touch far more than just lips, and possibly get all nekkid !

Depends who you are kissing, how yu are kissing, and where you ae kissing. Too many variable to consider.

Oxytocin levels should rise [en.wikipedia.org]

The left brain is logical and scientific. It has no place in kissing. The right brain is creative and emotional. Use the right brain when kissing..

Men make this mistake often. ... When kissing, you should be feeling, not thinking lol