Today we picked our roommates for Iraq. Just as the room choice lottery is the biggest event at every campus, and in Harry Potter's world, figuring who will be your roommate in Iraq is a very big deal.
And just as college room draw goes by class and sometimes by grade-point-average, our roommate choice has several restrictions. At least in our platoon, people of the same rank room together. When there are odd numbers, soldiers can room with someone one rank above or below, but not two. And just as in college, you want to pick a roommate you really like first (we call them battle buddies). Failing that, you want to pick a person you feel like you could get along with or at least would not be too judgmental about your flaws.
But the big drama is avoiding rooming with a soldier you don't get along with. This may seem silly for people going to a war zone, but if you have to spend most of a year in a place with a lot of stress, it is important not to have more stress when you get time off.
We don't have a Sorting Hat like Hogwarts Academy, or an sorting algorithm like college deans, so roommate selection is handled by several sergeants, a group that currently shares one large room and is know collectively by soldiers outside the platoon as the Fab Five. Cliques, whether in high school, college, the Army or at Microsoft Corporation, almost always have that kind of name from outsiders.
All this applies only to the male soldiers. Some different process governs roommate selection for the female soldiers.