1. Going to the toilets with a buddy, with the intention to both do a Number 2.
2. Bumping into a friend whilst both taking a dump in adjacent cubicles.
1. Lenny: "Hey man, rendez poo in 5."
Carl: "Yeah, that Indian food'll be catching up with me any minute."
2. Stu: "La la la, sitting on the toilet..."
Brian: "Hey, Stu, is that you?"
Stu: "Talk about a rendez poo"