But she is an old hand at this type of encounter and tells me she's met many men through the site, and that I was probably the only one who hadn't lied about my age."Sophia" tells me she thinks relationships have a shelf life of about ten years before boredom sets in, but that she stays married to ensure her children have a stable home.
In order to fit in with the general ethos of the website I have invented a wife.
Our relationship, I note, has suffered because we don't spend enough time together (not surprising really, since she doesn't exist).
After a quick search, I get the measure of the women on the site.
"My preference is for a man who is much younger than me with rugged features," says one. This is a way of paying someone a compliment without typing out the words. And over the course of a week I get almost 100 replies, messages and propositions.
But if I'm going to find out what really makes these women tick, I need to leave the safety of the virtual world and see them for myself. I arrange to meet a 41-year-old mother of two who misses "romance and flirting", in a cafe in two days' time.
She has declined to tell me her name, so I have to think of her as her web sobriquet.So I paid £119 for a month's membership, giving me an entre to thousands of faithless females.They are allowed to sign up for free as a way of ensuring the numbers are balanced between the sexes. "I want a man with a personality and looks to take my breath away." These are the requirements of the dark-haired, dark-eyed, 37-year-old Asian beauty who has sent me her romantic wish list.Reading it on my laptop in the aptly named Cafe Affaire in central London, I consider what she really wants: a no-strings-attached sexual relationship.After discussing how mundane marriages become and avoiding questions about my personal life, it's clear we're past our sell-by date after ten minutes, never mind ten years. She doesn't want to discuss her husband, and I feel uneasy talking to her.