There's always that one person who is never able to stay with the rest of the group. You don't even know how they do it, they're stealthier than a ninja and although you were JUST talking to them, you've turned around for a second and now they're gone. Every hour someone is allocated the role of babysitter for your wandering colleague, not because you're concerned for their safety, but you're more concerned for the reputation of your company. You don't really want them to get caught peeing on top of the bar, it hitting the media and you're never going to be allowed back into your favourite after work haunt.