First there were the “enjo kosai” Internet sites where underage girls hook up with adult males in exchange for money. Now there’s a new type of Web site that unites girls running away from home with men offering a place to stay in return for sexual favors.

Called “iede saito,” or runaway sites, and potentially harmful to children, they provide a forum where messages posted by runaway girls asking for a place to stay are answered by men.

Observers say such sites have emerged because the operators and male users want to dodge new laws on “deaikei,” or “encounter sites” (where members of the opposite sex can meet), that ban people under 18 from using them, diminishing the chance they will attract underage girls.

“If you regulate one type of Web site, users will go to another,” said Atsufumi Suzuki, an expert on Internet activity. Runaway sites first emerged about five years ago, he said.

With online encounter sites flourishing as a hotbed for sex with minor girls seeking pocket money, a law was introduced in 2003 that bans under-18 users and, since last year, requires site operators to register with authorities and confirm the identity of their users.

Another law regulating Internet use by minors was passed in June, this one requiring that cell phones used by children under the age of 18 block sexually provocative sites, although their parents can switch this feature off.

These regulations do not apply to runaway sites, which technically carry messages only seeking accommodations.

One message posted on an online bulletin board for runaways last month stated: “I am a high school student in Osaka. I’ve been living in an Internet cafe, but I don’t have any money left. I am prepared to do anything.”

A response reads, “I live in Kyoto but I can come pick you up.”

The runaways refer to the men as “kami” (god) and themselves as “kamimachi” (god-waiting).

A 17-year-old girl named Eri in Kita Ward, Tokyo, told The Japan Times she used a bulletin board to find the man who put her up and fed her for five days during the summer holiday in August.

The girl, who withheld her surname, said she fled home because her older brother was causing trouble and her father was violent. She stayed with the man in Saitama Prefecture for five days and slept with him during that time. She believes he was in his 30s.

“I just wanted to get away from it all, they were being so annoying,” she said.

While many of the runaway girls are not seriously harmed by their hosts, in some cases it can lead to sexual violence or confinement, said Tetsuya Shibui, a freelance journalist who wrote “A True Account: Underground Web Sites Crime Report” (“Jitsuroku: Yami Saito Jikenbo”).

Last year, 724 people under 18 were victims of real-world crimes such as rape in connection with encounter sites, while 792 youths were victims of crimes that stemmed from other types of sites, including runaway sites, game sites, profile sites and social networking sites, according to the National Police Agency, which released such figures for the first time this February.

There is no official figure for the number of runaway sites, but experts estimate there are currently about five runaway bulletin boards, while many posts with this kind of content are also found on nondedicated bulletin boards.

There are also around 50 sites run by encounter site operators, some of whom act as agents for prostitution organizations that dispatch call girls pretending to be runaways, according to Shibui.

The runaway sites attract girls from unhappy households who are prepared to offer sex to strangers for protection and sometimes money, Shibui said.

“Until recently, runaways were ‘yankees,’ slightly bad girls, who already had such networks, but now good girls also flee home and they don’t have these networks,” he said.

The sites also provide a solution for girls who want money but cannot find work in the entertainment industry due to strict age restrictions, he said.

The police are urging the operators of runaway sites to self-regulate, according to the NPA, but such clampdowns are ineffective because operators will simply start up new types of sites, according to the Internet expert Suzuki.

“It is hard to find a simple answer since it involves family problems and sex-related issues, which is why there is a tendency to blame it on the Internet, but that is only a haphazard solution,” he said.

Experts say the emergence of the runaway sites is a reflection of the behavior of minor girls nowadays, who tend to be less resistant to sex and see it as a bargaining tool to secure protection.

According to a 2005 survey by the Japanese Association for Sex Education, about 30 percent of girls between the ages of 15 and 17 attending high school said they have had sex, 6 points more than in the previous survey in 1999. The report sampled 1,093 high school girls nationwide.

Offering minors a place to stay and having sex with them is illegal under various laws. Sexual activity with anyone under 13 is a crime, while it is also illegal to have sexual relations with someone under 18 if money is exchanged.

It is also forbidden in many prefectures for minors to stay out overnight without parental permission.

Since 2006, at least six men have been arrested for engaging in sexual activity with girls they met over runaway sites. Company employee Keiichi Koma, 31, was arrested last month by Tokyo police on suspicion of performing obscene acts on a 13-year-old girl.

But in other cases, it is difficult to clarify the nature of the relationship, as some men do not demand sexual favors or pay, and a runaway might be given a job that technically makes her an employee, Shibui said.

The men offering accommodations tend to be in their 30s, but they are not necessarily single, and some genuinely want to help runaways, according to Shibui.

“One might be lonely during the few days his wife is on a business trip, and it’s a choice between a runaway girl or ‘delivery health’ (call girl service). Then there are some who fled home themselves as kids, and they are genuinely worried about the girls and do not necessarily demand sexual favors.”

Observers say runaways use the sites instead of turning to friends or relatives because they fear being discovered. Some stay with the same man while others flit from one to the next, sometimes by recommendation from fellow runaways or by being passed around between men who make the arrangements online.

In some cases the girl has no intention of returning home and the parents don’t press the matter.

One such runaway that Shibui met was a 15-year-old from Kanagawa Prefecture whose parents had divorced because of domestic violence. The girl, whose name he withheld for privacy reasons, had left home with her mother but preferred her father, and fled home a year ago to live near him.

She still attends school and her parents are aware she is living with strangers, he said.

“The parents think, ‘at least if she’s in school she’s alive.’ If they tried to force her home there would be trouble and then she might not even go to school.”

Shibui added that not all parents apply for missing person searches — because they would have to inform the police of their domestic troubles.

According to the NPA, applications for missing person searches were submitted for nearly 20,000 runaways aged between 10 and 19 last year.