ka kaw ka kaw
When on is on a double date and during this date they have to take a shit.  He uses this saying to inform the other person that he does indeed have to shit.  Expecially when one is all dressed up.    
Alex: man....i have eaten a lot at dinner tonight
Lindsay: Yea it was s0o0o0o good
Alex: Ka Kaw Ka Kaw
Lindsay: what does that mean?
Nicky: ha ha ka kaw ka kaw also man
Taryn: WTf guys wat does that mean
Alex and Nicky: you girls do NOT want to know  