Dating Rules Revisited

So I ponder what the current rules of dating are.

If I am dating a girl, and I kiss her, does that mean I shouldn't be going out on other dates and kissing other girls? What if I go to 2nd base, 3rd base, etc? At what point is a person a dirty rat?

Its somewhat up to the person I suppose. It seems some women feel that if you are kissing one girl, then you shouldn't be dating anyone else. To me that sounds a bit draconian. In fact, you could be sleeping with one girl, and still be dating around. It all depends on the mutual agreement right?

Or is there an implied agreement when things get to a certain point? Hmm... its tricky for shure (note the spelling of 'sure' in honor of Tombo).

I ask this because I wonder if I'm being a bad guy. I'm not serious with anyone, but maybe with one girl it is getting a tiny tiny bit more serious, such that I feel somewhat odd that I invited another girl to my xmas party, and still go on dates w/ other girls. Juggling dates.. its not too good. It may be a sign that I'm not into this girl enough.