Legal issues about Porno sites

[googlesuccess]

I am a resident of Japan. I have recently got an offer to make a porno website for Japanese girls in English. This propsed site will sell services such as X-rated pictures and movies which can be downloaded by the members.

However, before accepting this offer, I'd like to make sure about the various rules and regulations regarding international porno sites.

Also I'd like to know reliable payment processors which accept credit card payments from such adult websites.

I'd appreciate your comments. Thank you.