Regular visitors to Thailand will know the sight well: a wealthy, older Englishman arm in arm with the attractive Bangkok bar girl for whom he has fallen. Unfortunately, for 41-year-old, Marlborough-educated Toby Charnaud, his Oriental fantasy ended in bloody murder, according to reports now emerging from a Thai court.

Among the accused is his ex-wife, Pannada Laoruang, whom Charnaud met - yes - in a Bangkok bar, having sold his £2.5 million estate in Wiltshire to go travelling. The couple married in 1997 and lived for a time with his parents in England. When this didn't pan out, they returned to Thailand, where Charnaud bought two bars in the resort of Hua Hin.

They had a son, Daniel, but Pannada's gambling habit and £50,000 debts drove them apart and the couple divorced, with Charnaud gaining custody of the boy.

Toby Charnaud was murdered, presumably for his money, after being lured to Pannada's remote border village to see his son, who had been visiting his mother.

There, he was greeted by five men who, it is alleged, clubbed, shot and hacked him to death. His corpse was then burnt and the remains strewn across the jungly countryside.

It is a uniquely horrible story. Yet the impetus that drove Toby Charnaud to give up his life in England and risk his happiness in the arms of a Thai good-time girl is not unique.

Many Western men take inordinate gambles with young South-East Asian women, the kind of gambles they would never consider at home.

Why? Obviously, there is a physical attraction. For many Western men, the slender, petite, ever-youthful figures of Eastern women can be seriously alluring. Then there is a cultural aspect: Thai women have a grace, a femininity and a deferential sexiness that many women in the West appear to have forsaken.

The attraction of female submissiveness might be reprehensible, but it is none the less real. Who doesn't like having their clothes washed, their meals cooked and their brow smoothed by a soft and loving hand?

Yes, I know the temptation well. For something not entirely dissimilar happened to me, another thirtysomething Englishman, a few years ago.

I was holidaying on the Thai island of Koh Samui and in a noisy bar I met Sunee. She was pretty, 25 and great fun - one of those seductive Eastern women who inhabit the blurred moral zone between party animal and prostitute.

And I fell for her. It was more than a holiday romance and, when the time drew near for me to leave, there were tears from her and regrets from me.

Two dizzy weeks after we met, I had to fly home. I kissed Sunee, said goodbye and heard very little more for nearly half a year.

Then, out of the blue, I got an e-mail from her. "I have something to tell you. I am five months' pregnant." My head swam.

What should I do? My friends were divided. Some told me that I should forget about the woman. How did I know she wasn't scamming, fishing for money? Others advised me that I had to do the right thing. I had to ascertain if this baby was mine.

Four months later, that is what I did. I flew to Bangkok. Sunee and I had arranged to meet in my hotel. When she knocked on the door, she was carrying the tiny newborn.

Then she started crying. I hugged her, wordlessly, because I didn't know what to say. I didn't feel great passion for Sunee any more, yet I wanted to do the right thing. Whatever that was.

Then I cradled the baby. It was shattering. I hadn't expected the overwhelming emotions, the conflicting sensations that flooded me. I was 38, childless and single. Now, here was this perfect, vulnerable thing in my hands. My son, maybe.

Somehow, I got a grip. Before I had flown to Bangkok, I had established the best method of DNA-testing a baby. This, it turned out, was the "buccal swab" method.

You sweep a cotton bud across the inner cheek of the child's mouth, gathering cells. Putting the baby on my lap, I got out the cotton buds.

As I did, Sunee looked at me sorrowfully, perhaps contemptuously. It wasn't hard to sense what she was thinking. "How can you do this? How can you not trust me?"

I steeled myself and scraped the cotton buds, and sealed them in an envelope, which was then dispatched to a genetic-testing company in Britain.

Then I waited. And waited. I spent days sitting by my Bangkok hotel swimming pool, fretting. Half of me wanted this adorable child to be mine. Yet I had to find out the truth.

In the end, I couldn't help myself. Before I got the DNA test results, I went to see Sunee and the baby one more time. I had resolved not to do this because I was scared of the unmanageable emotion, that upwelling of paternal love.

It was a long drive across Bangkok to her tiny flat. There, I sat with Sunee and the child. We chatted and sipped tea, and I helped her feed the baby.

As I did, I started marvelling at the boy. Weren't those my eyes? Surely that was my nose, my mouth, even my Yorkshire complexion? Why did I need to do a test when I could see with my own eyes: this was my son.

I very nearly cracked. Back at the hotel, I decided to cancel the DNA tests and accept the child as mine. But when I picked up the phone, a small voice inside me said: "No, this is wrong. You will always have doubts if you don't find out now."

I put the phone down. The following day, the results came through. "We are 100 per cent sure the alleged father, Will Jory, is not the true father of this child." The boy wasn't mine.

My first reaction was anger - at Sunee, at life, at myself. I refused to see Sunee or the baby before I left. When she rang in tears, I rang off. On my return to London, the anger slowly abated.

It dawned on me that Sunee had convinced herself that I was the father because she so desperately wanted me to be the father.

The timing was right, she had my e-mail address, we had sort of fallen in love. And she was a single and frightened young mother, without any options. I understood.

But even when the anger had gone, the melancholy remained. I felt like someone had given me a son and then snatched him away. I was aware that my feelings were irrational, but that was no help. I was bereft.

Over time, however, these feelings mellowed. Two years have passed and now I think very differently.

As I see it, much of what happened was my own fault. After all, it was me who fell for Sunee so hard that I stupidly dispensed with the usual precautions when we had sex.

But why did I do that? What is it about young, seemingly vulnerable Thai women that makes so many Englishmen take such absurd risks?

For as poor Charnaud and I discovered, their submissiveness can come at a cost.

Thai women often see their older, wealthier white partners as saviours in all situations, such as pregnancy or gambling debts. And when the saviour fails, the reckoning can be painful.

For many, the Oriental fantasy should remain precisely that.

Some names have been changed.