Japanese men enjoy the nipple play, apparently.

Great article at the link about the sex lives of couples in Japan. Culturally fascinating. The statistics were pretty interesting.

Kirainet.com - A geek in Japan:

"I’m gonna show some captures I got from a girls magazine called Anan that made a sex special edition some months ago. This magazine made the special with some collaboration from the Japanese Government try to incite Japanese girls to practice more sex and give birth to more girls (One big problem in Japan nowadays). At the first part of the magazine they explain the girls how to turn on their boyfriends, another part is full of typical questions with explanations from an expert and the last one if full of interesting charts.

...Going back to the reasons why Japanese are so sexless, I already talked about some fo the cultural reasons and in the comments we could discern one of the other main reasons, it happens that around here they are pretty good cheating on their partners. I don’t find any data right now on the Internet but a watched in a TV show that after Italy, Japan is the country that likes more adultery. In the same TV show they explained an interesting phenomenon, in other countries like Italy, people’s infidelity usually lasts only one night (A crazy night), but in Japan infidelity with can be very long. Instead of a casual affair, they like to have an extra sexual partner that is not their wife.

For example, in a typical Japanese TV drama the script could be “A married man with children meets a girl in a crazy night, he likes it and gets her telephone number. He keeps meeting her and they finish doing nasty things. At the end he falls in love and one night having sex without condom she gets pregnant. His wife notices that there is another girl when she finds out that there is another kid in the school that calls ‘father’ to his husband. The wife is sad, but she doesn’t get really angry, what she does is to find a young guy on the internet using Mixi and… “. If you compare this with a South American TV series where the pattern could be “Married man has one night sex with his wife’s best friend. They never meet again but after six month his wife notices that there was some kind of infidelity. She decides to kill her husband and her best friend “.

This TV example should have explained many things about how affairs work in Japan, and how do Japanese girls react when they discover it (Is not that they are happy about it, but their reaction is not so exaggerated as we could expect from a western woman). Of course, for the lazy guys there are many places where you can go, in fact there are so many kinds of “sex clubs” in Japan that you need entire books to explain it. For the girls there are not so many services but there are starting to be many websites designed with the purpose to make your 不倫 (adultery) successful. This type of websites are used by frustrated married women, but it seems that the most popular method is to use Mixi the most used SNS in the world."