Contrary to populary belief, a Rogue isn't the same as a Thief. Rogues like to keep to themselves, although they aren't opposed to travelling with companions (they just don't sit right next to the campfire). The Rogue is really only interested in themself, but take advantage of the benefits of other party members.
They have quite a few skills similar to the Thief and Ninja (picking locks, camouflaging, trap detection/disarming, climbing, dodging, etc.). In addition, they also have a Backstab Attack skill that allows them to do greater damage to an enemy from behind.
Because of their actions often requiring nimble reflexes, they specialize with leather type armor.
Finally, Rogues have a special skill called Urban Sense that allows them to detect danger and other "events" that may happen in urban environments.