Fenris doesn't like to see Will like this, it usually meant whatever monster lurked in the man was stirring. He remembers the young days of being a Vampire when Will was still out there with his maker causing chaos. Remembers the older black court members talking about taking them out, but they decided it too late he remembers--

Will's words knock him from that memory as he listens. Of course the boy was asking about manipulation.. but why red in particular. What could be motivating the boy. It was something important, but what was questionable at the best of times.

"He knows his velvet smiles don't work on me, I see his darkness because he barely hides it from me, he tries to cut me with his knives. Perhaps because he thinks it gives him an edge.." It doesn't. If anything, it makes Fenris consider putting him down before he has a chance to 'come into himself' as Will puts it.