Ah yes, the issue of height is always being brought up every now
and then.
Vertical height does impose some problems when trying to kiss. Both
parties would feel awkward due to the altitude difference, and
perhaps shift in air-pressure should either party decide to
increase/decrease their vertical standing.
The simplest solution, that comes to my mind is of course,
converting the vertical height, into horizontal distance. While
vertical displacement would have to be calibrated by defying the
laws of gravity, horizontal distance can be easily compensated. Of
course, kissing in a horizontal position, can often lead to other
more............ creative forms of passion.