Big pimpin', Pedlo!
I remember one time seeing three younger Jap guys off after dinner. The next morning just 2 of them came to the office. I asked where the third was and I got "he had to go somewhere". I didn't buy it, told them that if there was a problem then we could try and help but they insisted so I didn't push it.
Then about 11am, I got a call. They gave my name and said that some drunk Japanese guy had left his laptop with his wallet and passport in it in one of their cabs - coming back from Patpong no less. Luckily he had one of my business cards in his wallet, so they were able to get in touch.
So I saunter back to the other two - "You sure xxxxx-san is OK?", "yeah, he's fine" they replied. "So there's no problem at all then, nothing I can help with?" - "No really he's fine, he had to go to a meeting is all".
"So he's not at the Japanese embassy getting a new passport then?" - man - I wish I'd had a picture of those guys faces when I dropped that bomb. Priceless.
I never did tell them how I knew or that the taxi firm called me - to this day, those guys think I have mystic powers.
Japanese guys are pretty cool once you get over the cultural stuff - just treat them like you treat anyone else and you'll get on famously.