How about multi-boxing and bots ?
You're not allowed to use any form of program to control multiple characters at once. You are, however, allowed to be logged on, say, two characters. The only thing we allow multiple characters for, is professions and banking, this means you cannot /follow level 2 characters at once. This will result in a ban of one of the two, and if repeated, both. It is also not a problem if you are, for instance, three family members in the same house, playing at the same time. Each multi-box case will be judged individually, so don't worry if you're not doing anything wrong.
What you can't do, is PvP with multiple characters, Dungeon with multiple characters, Raid with multiple characters, etc.
If you are two people playing two characters - no problem. If you are 5 people playing 5 characters - no problem.