The rules of Bisou are pretty simple. Girls Bisou everyone and Boys Bisou with girls.... But wait a minute sometimes boys Bisou other men. What are the rules on that??? How to men/boys know when they can/should bisou with other men/boys? Close family -- yes, but what about friends? How "friendly" do you have to be to bisou with another guy? A was recently "bisoued" by a friend that we met in November. We see each other every other month or so... How do you know when to take the relationship to the bisou level?
Also, I feel like the rules break down when outside of France. Sometimes French people will always want to bisou, but others don't and if you go in for a bisou, it can get awkward.
Sending out air bisous