umm....

I hate to agree with EE, but unless the culture around me has been changing at a quicker pace than I know, he's more or less right about the cultural expectation in the United States right now, and probably in most of the world: that adult sexual relationships are expected to be exclusive unless explicitly indicated otherwise.

(I am talking about actual relationships here, not people hooking up at bars for one night stands, where it might be implicitly understood that there is no real relationship involved. Nor am I saying that there is not a growing interest in non-exclusive relationships, only saying that this is not yet the norm rather than the exception.)

There are doubtless a few localities in the U.S. where other rules apply, but exclusivity in relationships is still the norm.