I'd like to hear a little bit about Japanese drinking culture, like: how do you invite people you have met but don't know really well to go to a restaurant or bar and eat and drink with you, while giving them plenty of opportunity to back out politely? What kinds of conversation is acceptable, for people who don't know each other real well, and for those that do? The Japanese seem to always have a correct way to do things, what are they for this kind of small group gathering (like no more than 6 people at max)? Any light you can shed on this before I get there and start observing in person? Just to be clear, I'm not asking for "Just say"iishoni nomimasen desu ka?"" type of answer. I want to know how to socialize with smart, mature young(er) people.

Thanks, peoples.