Informal Relationships in Japan?

Question:

I tend to research a subject before asking a question. But in the study of any culture, the things that are most obvious to a native are the very things that are least likely to be explained anywhere. I wish I could go to Japan and learn first hand but I don't have the means yet. So at the risk of seeming a fool.

Which relationships in Japan are considered informal? Obviously there are family and friends, but what about extended family like your aunt off in another city, your classmates, your brother's friends, people you hate, etc?
Also what are the differences in behavior? I assume you still use honorifics with your family and friends -- or at least some of them -- but there is no sort of bowing. Am I right? Please correct any misunderstandings. And what are the other behavioral differences?

Answer:

It depends on what you mean by formal.

In fact, it depends on how close they are. So the formal relationship at first, will be informal after some time. So there is no general rule.

Another important thing is age. If someone is older than you, you must behave formally.

>but what about extended family like your aunt off in another city,

It depends on age and how close as I said.

>your classmates, your brother's friends,

These are just like friends. No formality. But it depends what you mean by formal.

>people you hate, etc?

If you hate someone, you don't need to talk to them.

>I assume you still use honorifics with your family and friends --

What kind of honorifics are you talking about?