This graying, stooped man has been the Hangdogs' master dog trainer for many years. He doesn't live in a house like the others in the town. He prefers to sleep out in the open with the dogs under his care. He does have a lean-to in the park which he takes shelter under during those rare times it rains.
He keeps his dog-training techniques secret, but a charismatic Prisoner will be able to get some of his secrets out of him. He picks which dogs are taken to be sold, but he will also sell directly to visitors if he feels they might make worthy companions for his dogs.
The Prisoner has the option to obtain dogs from Teacher. Some dogs are just attack dogs, additional fighters to support the Prisoner and the big-boned dogs are pack dogs. The Prisoner may also use these dogs to carry extra stuff.
If he so chooses, the PC can do a couple of things with the Devil Dog if he's a CNPC. First, Teacher will ask the PC to allow him to breed the Devil Dog to improve the quality of the Hangdogs' canines. Second, the PC can ask Teacher to train the Devil Dog. This will increase one or two of the Devil Dog's stats.
Teacher is intended to be a likable figure, which generates emotion if Caesar's Legion comes to deal with the Hangdogs for not delivering Blackjack as promised, because all the dogs in the village will be slaughtered, and Teacher will lie dead among them after trying to stop Caesar's men.
Teacher has not appeared nor is he mentioned in any published game. He was to appear only in Van Buren, the canceled Fallout 3 by Black Isle Studios. It is not certain if he will appear in any future Fallout game.