I am not 100% familiar with college dorms, so I have to go with the "typical Hollywood" ones. Large building with multiple floors, divided by gender (if not different dorm buildings) and mostly arranged that freshman share rooms with one another, but since people drop out or change courses over time, sometimes you end up with a senior(?) or so. Rooms are usually designed for two, with exceptions. If Sumat explained his rather large physiology, he probably received a room for himself...