Watchout, there's monstrous at your back !

is this a bug or ... ?
when i get torian kel, there's nothing happen with the people, i can still talk with other, though torian kel is evil alignment, and then after i get z'an a'lurin, still i can talk, but when z'an alurin alignment goes good, all the "criters" in arcanum wont talk to me again, they shout "Watchout, there's monstrous at your back !" i can't buy anythings when i with z'an alurin, so i just kill the shopkeeper !

 

I think it has to do with the Magickal Aptitude of yur followers. It's not just because they're bad, because Jormund has gotten the same reaction.
There's plenty of anti-magick bias out there.

 

One time I had Geoffrey, he had on barbarian armour, and shopkeepers refused to talk to me unless i had Geoffrey wait.