AFTER A FEW years, the strain of living in the world’s politest and least confrontational society really takes it out of a man. Which of us, from time to time, does not relish a healthy argument or a nice, tension-relieving screaming match? And yet in Japan the simple pleasures of invective, sarcasm and rudeness are cruelly denied.

This is a country in which someone who is incandescent with rage will, as a very last resort, denounce his antagonist as baka — a word no stronger than the word “fool”. While an English speaker can choose between “Put a sock in it”, “Shut your mush” or “Zip it”, Japanese is restricted to the anaemic urusai, which means nothing more than “You are noisy”. It is claustrophobic to find oneself in a country without insults — or that is what I thought until I encountered the work of Ryunosuke Kita.

Mr Kita (or “kitaryunosuke”, as he signs himself) plays a unique part in my life — he is my conscience, my nemesis and the closest thing I have had to a stalker. Early every morning, he logs on to the websites of the British newspapers and the BBC. He is interested in China, the Middle East and in coverage of Japan by foreign correspondents — especially, it seems, in articles written by me. These he carefully translates into Japanese and posts on to his weblog accompanied by the most violent and inventive abuse I have encountered in Japan.

It truly restores your faith in the Japanese language reading the things that Mr Kita writes about me, and his blog is an education. He’s called me a baka, of course, but that’s only the start of it. I have been denounced as a “charlatan”, a “rotten devil foreign reporter”, a “low-class foreigner” and — perhaps my favourite — “the private parts of The Times”. “I have just realised once again,” Mr Kita sighed, after a piece I wrote about North Korea, “this guy is a totally stupid foreigner with no talent for research.”

How to deal with such a person as myself? Mr Kita has plenty of ideas, which are in themselves informative about Japan’s history and culture. “He should be arrested for lack of respect for the Japanese Imperial Family,” he opined in February. “First, bind his limbs and parade him around the city limits. Then flog him a hundred times.” These are not random suggestions but learned references to prescribed penalties for treason during the Edo Period (1603-1868).

Kita-san knows our own culture as well, as illustrated by this well-informed commentary on the British Royal Family. “The husband of the Queen makes stupid comments wherever he goes, and the Queen is regarded as an old biddy,” he observes. “Her former daughter-in-law . . . tried to marry a rich Arab parvenu and was killed. Her (Diana’s) husband was hooked on an older woman who introduced him to sex, and got divorced to remarry. His younger son was criticised for wearing a Nazi arm band.” I couldn’t have summed up the Windsors more pithily myself.

The most ingenious thing of all is the brilliant formula that he has come up with for spelling my name in Japanese. The closest the language can come to my tongue-twister of l’s and r’s is Richaado Roido Parii. My cyber stalker has devised a way of spelling this out with characters which literally mean “Old Stomach Bloke Infected with Plague”.

“Hey, Old Stomach Bloke Infected with Plague,” he urged after some reporting I recently did from Bangkok, “just drop dead in Thailand, and don't come back.” On Friday he even posted a photograph of me on his blog, above a caption referring to me as “a Welsh mountain monkey”.

Apart from being amusing, Mr Kita, as you will have gathered, is a xenophobe. He hates anyone who doesn’t agree with him. He hates Chinese and Koreans. He lives in a universe in which the word “foreigner” is in itself a stinging reproach. Japan is such a gentle, soothing place for so much of the time, and its people are so mild and friendly, that it is salutary to be reminded that, like every country, its has its share of bigots, trolls and nasty pieces of work.

The marvellous thing is that Ryunosuke Kita (I’m sure that’s a pseudonym, by the way) is reading this right now. And so I offer him a challenge — come out from behind your blog and meet me face to face. Are you man enough to look the Old Stomach Bloke Infected with Plague in the eye? If not, then I have only this to say to you: Fool! You are noisy!

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