My girlfriend is tall to begin with, then she puts on some stilt heels and is the same height as me and I need to get a step stool to put mistletoe over her head so that I can kiss her. The step stool to physically kiss her and the mistletoe to, ya know, allow it or something.
'Hey, you're under a twig, let's make out.'
I bet that tradition started with a horned-up botanist in Scandinavia. Sounds like something a Scandinavian botanist invented when the sun didn't come out for 6 months and folks started getting fidgety.