Twitter user @MarvClowder had an interesting question during our liveblog/livetweet of “Inugami,” with regards to why it’s the involuntary emotional reaction that only Grimms and other Wesen can see, versus the intentional, controlled reaction. Since the Wesen is out of control in the first instance, shouldn’t anyone be able to see the woge?

I confess I was drawing a blank on this one, but Admin D (@irreverentcatalyst) has, once again, come through with an answer (which I have typed up because she doesn’t feel like it).

The answer is that it has less to do with what the Wesen is intending in the first (emotional, involuntary) instance, and more to do with the biology of a Grimm. To make it a little clearer, let’s put it in terms that make a little more sense in our world.

Think of it in terms of pheromones. Imagine a living creature (a Wesen) that gives off a pheromone. Now imagine that only certain other living creatures have the genetic marker that allows them to perceive it (Grimms).

It’s an involuntary action, something done without intention and without control, but it’s still also something unnoticeable unless you have the biology that allows you to pick up on it (like the extra cones in a Grimm’s eyes, for instance).

A good example might be certain animals being able to sniff out our fear. Our adrenaline gives off an odor they can perceive, but that doesn’t mean any of the people in the room can smell that we’re afraid.

On the other hand, imagine a creature (Wesen) can intentionally give off a very pungent scent (like a skunk, for example) that anyone with a sense of smell can and will notice. Not a particularly flattering comparison for Wesen, but I think it gets the point across?