I'm sat in Brussels - in a curiously small pub known for its Trappist brews and popularity amongst bikeys, and I think I'm about to witness a bar fight.
Two large scowling men in motorbike leathers lock eyes across the room and head for each other, clenched fists, neither backing down.
Just as I'm searching for an exit, they meet and exchange three theatrical kisses on alternating cheeks.
Seeing my confusion, a friend explains "It's just part of the kissing culture."
The kissing culture: it's something eyed with deep suspicion in New Zealand, America and the Anglicised world. However, you'll find that we're in the minority.
The rest of the world is exchanging pecks on the cheek as readily with colleagues and friends as "how do you do?"
Like your great aunt's flamboyant air kisses, it's just something you will have to endure if you want travel through Europe, South America or even much of the Middle East.
But is it one kiss or two? Who kisses who? left or right cheek? The whole thing is a minefield of potential 'faux pas' designed, it seems, to trip up our reserved Kiwi sensibilities.
But don't worry. Get out your breath mints, because our guide to global kissing culture has you covered.
Turn the other cheek: origins
In his recent book One Kiss or Two: In Search of the Perfect Greeting, American diplomat Andy Scott speculates on where this extravagantly affectionate greeting came from.
"In his Epistle to the Romans, St. Paul instructed followers to 'salute one another with a holy kiss.' And so the 'holy kiss' became a common greeting among early Christians and a central part of Catholic ceremony."
It could be this exuberant locking of lips became a more modest kiss on the cheek in Catholic Europe – a slightly more sanitary and less flamboyant salutation than for the full-on snog with a stranger. Though this theory would explain why there are so many different variants across Latin America and Continental Europe.
Argentina, Chile, Colombia, Peru, the Philippines
Croatia, Brazil, Spain, Italy, Greece, Germany, Hungary, Romania, and parts of the Middle East (though mostly male/male or female/female)
Belgium, Holland, Slovenia, Macedonia, Serbia, Switzerland, Egypt and Russia (accompanied by a back-slapping bearhug)
In South America it can be customary to greet a new acquaintance with a kiss on the cheek. When locked in, you have no option but to commit. To fail to reciprocate the kiss on the cheek could be considered an affront, similar to as if you had refused a handshake.
The gender of your opposite number is also an important factor: in much of Europe and Latin America it's not uncommon for two women to exchange kisses, and male and female acquaintances to swap a peck on the cheek.
But not everywhere. In more conservative parts of the world and Middle Eastern countries this can be frowned upon.
While cultural differences are normally accommodated, it can be an awkward experience for all if one party blinks at the last minute leaving the other making-out with their lapel or – worse – overcommits and both pairs of lips meet in the middle.
Like the Argentine tango, if in doubt: it's best to allow the other party to lead.