Your picture can be viewed only if you give a password to the person with whom you are conversing.
The idea is presumably to safeguard people from searching for their own spouses on the site - though how a husband would explain to his errant wife how he came to stumble across her picture on a website for adulterers, I don't know.
It may sound like an unpleasant niche website for a handful of amoral people to whom wedding vows never meant very much.
But it claims to have more than 100,000 members in the UK.
Postings such as: "I want a man who can look after me and knows how to treat a woman. I'm surprised and unsettled by the forward tone of some of the material. Determined to avoid the connotations, I reply: "The Beatles." I never hear from her again.
One woman sends me a message heavily laden with sexual innuendo and I come to regard her as the mistress of the single entendre. Another woman's first contact with me included a plan for a day out together, including visits to art galleries, a stroll round a park and then "a few hours under the duvet". I'm later propositioned by someone who tells me she has an hourglass figure.
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.
Despite this, she still seems keen to flirt with me.
She seems rather on edge and sends me a text message at the time we're due to meet asking why I'm using the website.I register, and enter the murky world of two-timing technology, taking note of the warning on the site: "Not all affairs have a positive effect on a marriage." What a masterpiece of understatement.I wonder if anyone has ever read this, seen the wisdom of it and decided not to join. "I'm witty, charming, handsome and modest, and I'm kind to animals," I write, hoping this description will have a fairly broad appeal, and also include a recent photograph.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.