Japanese Women Run a Gantlet of Molesters on Commuter Trains : Harassment: Few men are caught because many victims simply flee. One survey found that three-quarters of women in their 20s and 30s had encountered a groper. New book by a groper is selling well.

Riding on a crowded commuter train, packed in tightly with other passengers, Yoko Kurihara felt a hand reaching inside her clothing.

But she did not confront her assailant. She simply fled the train at the next stop.

“I was so disgusted and shocked,” recalled Kurihara, who now heads a women’s group. “Groping doesn’t leave visible scars, but it’s no different from rape.”

Of all the forms of sex harassment faced by Japanese girls and women, unwelcome fondling on a crowded train is probably one of the most pervasive.

Violent crime is rare in Japan, but groping--ranging from rubbing up against a victim to thrusting an intrusive hand under her clothing--is an everyday occurrence, especially on crowded commuter trains.

A women’s group in Osaka, Japan’s second-largest city, says three-quarters of women in their 20s and 30s who responded to a questionnaire reported encountering a groper at least once. The victims said that fellow passengers, even if aware of what was going on, almost never intervened.

Confronted with a groper on a crowded train, few women cry out or resist--choosing, as Kurihara did, to flee instead. But their anger and disdain is summed up by the slang term for gropers-- chikan , or “idiot man.”

Fed-up feminists say train gropers are a telling example of the obstacles women face in their efforts to win fair treatment in Japanese society.

“Groping reflects nothing but sexism,” said Noriko Yamaguchi, a women’s rights activist. “Throughout history, our country has been too tolerant of men’s sexual misdeeds.”

Underscoring that tolerance, one self-confessed chikan has written a book about his experiences. Samu Yamamoto’s book, “A Groper’s Diary,” is selling well at Tokyo bookstores.

KK Bestsellers, its publisher, says 50,000 copies have been sold since it went on sale in April--about five times the average book’s sales figure.

In the book, Yamamoto talks freely about molesting an average of a dozen women and girls a day over the past 26 years.

A bespectacled 42-year-old illustrator at a sports newspaper, Yamamoto said he counted on women being too embarrassed to cry out--or too fearful of accusing the wrong man, an easy mistake in a crowded train car.

“I wouldn’t try groping in the United States because American women seem too tough,” he said in an interview. “But Japanese women tolerate us--or I’d be in jail by now.”

A convicted groper can be sentenced to up to seven years, but police say there is little they can do if women do not report assaults.

“Be brave and speak up, or they’re encouraged to advance further,” said Akito Mochihara, a Tokyo Metropolitan Police investigator.

But many women who have encountered gropers say shame and shyness caused them to simply freeze. Others fear retaliation.

One 25-year-old office worker, who did not want her name used, said she wheeled around and stared down a man who had been rubbing up against her.

He refused to meet her gaze, and quickly got off the train. But the woman discovered, to her fury, that he had first stuck a wad of chewing gum in her long hair.

Some women’s groups have urged the creation of women-only train cars. But East Japan Railway Co., whose trains carry 13 million passengers in metropolitan areas every day, has shown little enthusiasm for the idea.

Spokesman Akihiro Takimizu called the idea unworkable, saying it would make for even more congestion.

Even women’s groups acknowledge such a step would not address the underlying problem.

“Unless men change, this is the only way we can be safe,” Kurihara said. “But it’s not a fundamental solution.”

Yamamoto, for his part, said he has suffered few repercussions in his personal or professional life since going public.

He said that he got a few critical calls after a round of TV appearances to plug the book but that most calls came from young women wanting advice on how to foil a groper like him.

In the interview, Yamamoto displayed only one brief flash of awareness of the consequences of behavior like his. He recounted how his wife once came home and told him she had been molested on the train.

“I felt offended,” he said.