THANKS to this bad breath detector, there's nothing to stop you kissing - besides the knowledge that you're tonguing a pipeway to somebody's guts.

Mouths are confusing. It’s a well known fact that the inside of the human being is much uglier than the outside. A brief glimpse of televised surgery is all that’s needed to remind us that levering open even the most sculpted torso reveals little more than a fleshy swamp of lumps and gristle.

To keep yourself happy and sane, it’s best not to talk about, or even think about, the hidden grotesquery at the core of your loved ones. And yet there, slap bang in the middle of their faces, lies a brazen reminder of the tangle of guts beneath their skin. This great flappy hole - known as the mouth - leads directly to the innards, and it is nothing short of morbid. Its sheer versatility and usefulness are no excuse. In this age of superscience and genetic experimentation we should be campaigning for a less primitive solution to consumption and communication than a big toothy anus on our heads.

But tolerance for mouths is surprisingly high. There are even those who find them alluring, perverts who idolise pearly teeth, glossy lips and a broad smile to such an extent they find themselves able to ignore the pulsating, bloody horrors that lurk within. They kiss, these people, expressing their affections for one another by pressing the flexible openings on their respective jaws together in a sick and monstrous embrace, oblivious to the half digested lunch and biscuits lurking just tens of centimetres down the pipe.

It’s a mystery. Since moving into the shed, all our relationships have been conducted the proper way, over the internet. We use nothing more than vibrating USB chairs and an elaborate series of text commands. It’s clean, easy and totally risk free, provided you erase all traces of your identity the second your partner expresses an interest in an English visa.

There is, however, a new gadget which has faintly piqued our interest in mouths. Not because we like them, you understand, but because we like small pieces of technology that cost about £10. It’s called the Kiss Me Meter and it tells you exactly how hideous your facehole is on a scale of one to five. Measuring the amount of hydrogen sulphide in your breath - left behind after you eat - it calculates your stinkiness and lights up the corresponding icon, from a tragic smelling broken red heart to a healthy, whole green one. We’re not sure green hearts are technically healthy, but never mind.

Ours, of course, defaults to the broken heart whenever anyone uses it. At least it would if we allowed anyone to open their mouth near us. Filthy beasts.