At Dorian's clarification Fenris merely replied with a faint noise of disbelief. Not of the subject itself, but of the implication that the mage was attempting to be helpful with information. He knew very well he couldn't trust the words of a snake, for they often spoke truth in order to gain trust.

"Do not flatter yourself, I am not purposefully standing in your way." After all, how could he possibly know where Dorian was headed? And he wasn't large enough to fill the hallway anyway, even though it was narrow.

He simply turned so that the mage would have additional room, and his eyes were locked on him the entire time. If Dorian came within arm reach, Fenris would have the lyrium in his tattoos to briefly flash, just to see if it would frighten or provoke him.