the man is an idiot yet has no quest referance whatsever , nor does any of his house , his life is that of a recluse , never mentioned , never seen and yet if by some reason you just happen to stumble into his house he suddenly blurts out all the " low birth" stuff?
i have always felt that he was orginally supposed to be just a little something more , but ultimatly was just left as a token npc.
i see three things
1. rumours : i think he was orginally supposed to be mentioned in a rumour , you could speak about him as a option and the npc would tell you how high and mighty he is and sombody needs to "teach him a lesson" - this would eventually lead to you meeting him and having the infamous dual
2 . sepeate quest : exspanding on the first idea , however rather than just another rumour you may look into this does in fact activate a stand-alone quest, during the quest you have two options : to try and change him or kill him , if you change him his tone changes and he is seen regulary aorund town being nice , if you lose your temper he will wind up dead
3 . dark brotherhood: im sorry but this man just ozzes with DB contract clues - ruch, stuffy old man living alone , never leaves his house , clearly his attitude would make him a LOT of enemies
what do you think?
also the rat : could just be for testing , but something else?