You wouldn't have lived to make it out of childhood without the aid of a sibling, friend, or companion on whom you could always count to distract your enemies long enough for you to do a little bit more damage than normal. That companion may be another PC or an NPC (who may even be recently departed from your side). When you hit a foe you are flanking, you deal an additional 1 point of damage (this damage is added to your base damage, and is multiplied on a critical hit). This additional damage is a trait bonus.