Wow, there are a lot of good answers to this post. Interesting to read what the views are on when to leave. First off, just to let everyone know, my boyfriend and I are in an "open relationship". We love each other very much, no doubt about that. But at the same time it is hard to think of only being with ONE person for the rest of your life. The straight people have made that obvious with a 50% divorce rate.
But when I do a hook up, most of the time the conditions are set for what is going to happen before I get to their place. If I'm going to spend the night, I call my bf and let him know. Though 99% of the time when we are both satisfied sexually, I will get dressed and call it a night, get home, and cuddle up with the bf.