Board Thread:General Grimm Discussion/@comment-5301811-20160430205203/@comment-5301811-20160501004817

It could be that "pure" Grimms are so few in number nowadays, and were last seen and heard from so long ago, that Wesen like Monroe and Bud have either never heard of them to begin with or they've only heard stories about "those hideous pale, skeletal Wesen that vanished hundreds of years ago"; they don't know that these "urban legend Wesen" are actually Grimms. Also, in "The Walking Dead", Bud basically tells Juliette that Nick is like her, but a Grimm, which could be said of Wesen as well ("I'm like you, but an Eisbiber").

Wesen like Renard and Conrad perhaps know the truth; notice how Renard doesn't say anything concerning Nick after Conrad tells him why he might fit in. Maybe Renard and Nick's mom didn't want to tell Nick the truth before because they felt that he wouldn't be able to take it after having already slaughtered so many other Wesen and being told that he was technically the "good guy" for so long. However, if Renard gets into a fight with Nick either near the end of this season or whenever the BC arc is wrapping up, he could tell Nick that Grimms are Wesen to suddenly distract him from the fight.

And then, there's this quote by Nietzsche: "Battle not with monsters lest ye become a monster and if you gaze into the abyss, the abyss gazes also into you." The eyes of a Grimm turn black when seeing a Wesen woge, black enough to reflect it back to the Wesen. And if the Grimms do happen to actually be a type of Wesen...well...