In the story of Peter Pan we learn that a kiss is in fact a token given to someone. Wendy gives Peter a thimble, and in return he gives her an acorn button.
"I think it's perfectly sweet of you," she declared, "and I'll get up again," and she sat with him on the side of the bed. She also said she would give him a kiss if he liked, but Peter did not know what she meant, and he held out his hand expectantly.
"Surely you know what a kiss is?" she asked, aghast.
"I shall know when you give it to me," he replied stiffly, and not to hurt his feelings she gave him a thimble.
"Now," said he, "shall I give you a kiss?" and she replied with a slight primness, "If you please." She made herself rather cheap by inclining her face toward him, but he merely dropped an acorn button into her hand, so she slowly returned. Source: Project Gutenberg at www.gutenberg.net
Later, in the movie Hook, staring Robin Williams and Dustin Hoffman, we discover that a traditional kiss, two sets of lips pressed together, causes Peter to forget about Neverland, the Lost Boys and Tink his trusty sidekick. He instead becomes a regular boy and grows up as Peter Panning, not remembering his wild adventures as The Pan.