These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Arc Fatigue: The amnesia storyline, which was finally resolved at the end of season 2. Monroe went on to apologize for it during season 3.
Designated Protagonist Syndrome: A common critique of the show is that Nick is just not interesting, and the Monster of the Week format doesn't give him much opportunity to become so, as it inevitably involves him calling Monroe in to explain what's happening and overshadow him.
The writer's seem to have realized this, and for several episodes have taken the focus off of Monroe to allow for more character development and differentiation for Nick, who has gone from a typical cop-show protagonist to become more pragmatic and snarky, as well as coming into his own new identity as a Grimm/Cop.
Some fans consider this a strength of the show, since it is a nice reprieve from all the "special" or "tortured" protagonists which are especially common in Genre show. Nick being a normal boring person who deals with his new abilities without a lot of drama is one of the aspects which sets the show apart.
Eric Renard is quite dashing, when he's not having people tortured or killed.
Khloe Sedgwick, the Musai from "Kiss of the Muse," professes that what the men who fall in love with her do (obsession with her, violent rage towards any challengers for her love) is not her fault, but over the course of the episode it becomes clear she both encourages it and seems to enjoy watching it.
Fan Dumb: A lot of fans expressed outrage when Rosalee revealed to her mother and sister that her drug addiction landed her in jail, saying it derailed her character and came out of nowhere...forgetting completely that the first episode she was in established her background as a former drug addict. She even led Monroe and Nick to a local Wesen drug den she once frequented before getting clean.
Fan-Preferred Couple: Nick/Monroe and Nick/Renard. Nick/Ariel and Nick/Adalind are not as popular as the two previously mentioned ships, but they do seem to receive more enthusiasm from fans than the Official Couple Nick/Juliette and are gradually gaining more popularity.
Fanon: Lots of fans think that Monroe's full name is "Eddie Monroe" but Word of God says that's never been the case. As of "The Wild Hunt" his parents are using Monroe as his given name.
Genius Bonus: More like paying attention bonus, but Monroe brings up during Season 2 that he found his grandmother's antique picnic basket. What kind of wesen is Monroe again, and what well-known fairytale did one of those and someone with a basket feature in?
Nick calls Rosalee when he needs help with a Wesen medical issue. Monroe is jealous that Nick didn't call him.
When Nick and Monroe are talking about how they have to lie about their entire friendship to Juliette, it sounds more like they're talking about covering up an affair rather than hiding their supernatural natures.
When Nick walks in on Juliette hugging Hank: "Whoa, whoa, whoa! He's mine."
There's a mild undertone of Renard/Meisner and Renard/Sebastien (which is amusing when one of them seemingly gets jealous when Renard pays attention to the other - Meisner glares and puffs up, and Sebastien pulls out the puppy-dog eyes).
Jerkass Woobie: Captain Renard. He was born the son of a King to a hexenbiest mother, ostracized from the rest of his family. Then when his stepmother the Queen found out that he was a zauberbiest, she tried to have both him and his mother killed. They escaped to America, where he ended up as a cop. His family (especially his brother) has tried to kill him more than once. And that was before the business with Juliette and the zaubertrank. That was when the Sanity Slippage started, forcing him to reveal himself to Nick.
Magnificent Bastard: Captain Renard. He gets a rather amusing line in one episode where he deadpans "Yes, I am Royal, and yes, I can be a bastard."
Adalind is a Magnificent Bitch...maybe. Recent events may revert her to her old ways.
Narm: When Adalind meets Frau Pesche, probably intended, at least for the weirdness.
Frau Pesche: I knew your mother well.
Adalind: Me too.
Although, the tone of conversation suggested that Adalind was really not sorry to see her mother go and really wanted Frau Pesche to stop talking about it.
Each and every time Captain Renard speaks German. The man grew up in Austria, you'd expect him to get the syntax right, at least. Same goes for most other instances of characters speaking German, although Monroe is excused for being a third generation immigrant.
We don't know how much time Renard spent in Austria. He went to school in Switzerland (a French-speaking nation) and his mother is French-speaking. It makes sense that French is his stronger language. Also note that he and his brother spoke to each other in French, not German.
It's even more egregious now that part of the show is set in Austria - some of the guest stars are absolutely horrendous (and there are complaints about Sasha Roiz unconsciously adopting the accent of whoever he's speaking to).
One-Scene Wonder: Many side-characters like Hap, Roddy, Barry, Holly, and Bud The Fridge Repairman (before he was promoted to a recurring character) have gained following.
Valentina Espinosa and Ian Harmon were nowhere near them, but in way of growing into it.
Casey, a would-be victim in "Mr. Sandman". She actually does some pretty Genre Savvy things like covering her eyes against a wesen that targets them when he attacks her, gets a weapon as soon as she's able to, and ultimately is the one to defeat the wesen of the week.
This sticks hard for Juliette, and not so much for Hank (at first). Although Juliette could still rapidly head back to Scrappy territory. Actually, while many people love it, some people are complaining about the amnesia storyline, and, despite her good amount of fan love, some people are claiming Bitsie Tulloch is the weakest cast member.
Finally achieved for Hank "One Punch" Griffin in in Bad Moon Rising when he goes from freaking out over finding out about the Wesen - and that his goddaughter and best friend are one - to dropping a Coyotl (in full game face, no less) in one punch!
Rooting for the Empire: A minor example in the Bauerschwein. Twice we've had episodes casting the Bauerschwein as the villains in the Blutbad/Bauerschwein feud, but it's difficult to forget that the Bauerschwein have been on the receiving end of the Blutbaden's brutality for centuries. The only laws that could even begin to protect them are the Second Amendment and castle laws. Angelina brutally murdered two innocent Bauerschwein for sport and Monroe (who we're supposed to sympathize with) doesn't even bat an eye at it. And although the Bauerschwein's methods of revenge are definitely cruel, they're also pretty darn clever.
The Scrappy: Adalind, for some time until the penultimate episode she appeared in in season 1 showed that she had a Stage Mom and was a Love Martyr to Renard. That, Renard's Manipulative Bastard-ness and her elegant and carefully-thought revenge increased her popularity for a while. However, her vile intentions and careless actions towards her own unborn child are have begun to drag her back to this status. Not to mention her seemingly endless supply of stupidity she seems to suffer from and how long the monster baby storyline has dragged out, taking time away from the main storyline in Portland.
Juliette's been wavering in and out of this trope, but seems to have been rescued from it, albeit on a special way.
The actress playing "Mrs. Garcia" in "El Cucuy" is 54◊. Mrs. Garcia is 77, and the costuming department thought that the way they could age her up was giving her a ridiculous, cheap-looking wig◊. It looks worse in the episode - it looks unnatural and you can almost see where the wig ends and her real hair begins!
Handwaved in that old age effects are among the most difficult to pull off. And that said, much like La Llorona and Volcanalis, El Cucuy is presented or heavily implied to be extremely long lived. So while she may be 77 years old, it may not mean as much to her species as it does to other wessen and humans.
Squick:The less said about the frogs in "Lonelyhearts", the better. Or the rats in "Danse Macabre" who chewed off a man's face. Or the judge with a gavel shoved down his throat and the woman with her tongue cut out in "Game Ogre".
How Spinnetods kill their victims.
Not as bad as some other examples, but two words: Blood. Cookies.
Basically, if you're going to get killed by a wesen who isn't concerned about The Masquerade at the moment or you're bumping into a wesen engaged in some of the more instinctual habits... it's probably not going to particularly nice.
What Geiers are infamous for as a species - brutally harvesting human organs from victims that are still alive, be they wounded soldiers on the battlefield or homeless kids on the streets - and selling them on a Wessen black market that uses the parts like apothecary ingredients.
The Lowen underground gladiator ring feeding new contestants the remains of defeated fighters.
Let's also not forget how traditional Coyotl families "introduce" seventeen-year old female members to the pack. Which is not an introduction and just a way to sugar-coat gang-rape and incest.
Also in "To Protect and Serve", Nick falls into a pit of decomposed corpses. When trying to find his flashlight, he accidentally grabs rotten body parts.
In "Mr. Sandman" we get the image of a parasitic worm wriggling out of a persons bloody eye socket. Sleep well.
A pregnant Gluhenvolk's "pickles and ice cream" is apparently raw cow ovaries. Yum.
The hideous fate of Blutbaden who ate the "Black Despair" mushrooms in "Best Served Cold". Their helplessness and hopelessness are as horrible as their agony.
Tastes Like Diabetes: In "The Bottle Imp", the foster family that April is sent to live with have shades of this. The audience is not surprised when after five minutes of dealing with them, she puts on her Game Face and attacks.
Tear Jerker: Angelina's death and Monroe's grieving for her.
Averted in "La Llorona". Despite a majority of the characters in the episode being Hispanic and the main victim even only speaking Spanish, never are they treated as potential border hoppers or otherwise suggested to be anything other than US citizens. Or in the case of the special guest star - who has a strong accent - another police officer from the US.
"Nameless" features a female game programmer who apparently did not write the innovative code for her game. Said female also blows off the person who helped her and it's suggested she Really Gets Around. While this is all well and dandy for any other situation, considering the relative lack of females in the game industry, much less female programmers, as well as the very much macho/boys club culture of the industry, this kind of portrayal only reinforces the anti-female attitude in the industry/diminishes legitimately great female game devs and female technical experts in any field.
In general, if a wesen comes from out of town, they are almost-certainly to be a murderous sociopath subscribing to "the old ways," while those who are native Americans are usually either law-abiding citizens or "ordinary" criminals.
What an Idiot: It's probably not such a good idea for Adalind to be letting so many people know she's carrying Royal blood. Or for her to to trust Stefania so completely since the latter has already shown backstabbing tendencies. She never even asks Stefania to completely explain it to her; she only blindly follows instructions. Or for her not to think that the Royal Family just might be watching her when there's a camera inside her room! And then shunning and snarking one of the few people who may be able to help her if things go sour. And then when she is in a restaurant and she knows that someone is sitting behind her staring at her, she tries out newly discovered telekinetic powers. You know, two seconds after she's made aware someone is watching her. When her unborn child begins to kick unnaturally and starts causing her pain she waits until she's writhing around in agony before calling Stefania and asking for advice. And when told that she is facing an Express Delivery, she reacts not with the slightest bit of concern (and again, no prying questions) but with mere annoyance. In fact it might be easier to list the things she does that aren't idiotic.
Hap, the friendly Blutbad in "Three Bad Wolves" who gets killed over a blood feud he was never personally involved in.
Monroe is a Blutbad who lives apart from his family, likely because he has a vegan lifestyle while they still hunt. In "Three Bad Wolves" he gets caught between looking for vengeance of his friend's death and staying out of the fight to avoid escalating things to worse levels... even though that means his former lover may end up dead. Things go great for him for a while but now stands in danger of being disowned from his family altogether for loving a Fuchsbau.
Nick during Season One and Season Two. After he proposes to Juliette, she turns him down because she can tell he’s keeping secrets from her. Of course, he’s keeping secrets to protect her from the crazy dangerous stuff that he now has to handle. When he finally tells her, she doesn't believe him. It takes all of Season Two for things to be made right between them. However, with his new powers coming into play Nick is getting less pitiful and more of a threat.
Rosalee. She grew up different because she is Wesen. She pursued the wrong crowds to feel like she belonged. She ended up getting addicted to drugs and landing in jail, unknowingly missing out on her own father's funeral. She loses her brother to an armed robbery. Then she finally meets Monroe and everything is fine...for a while. She even manages to get reconciled to her mother and sister. But then she meets Monroe's parents. They turn out to be species purists who refuse to give their blessing to the relationship and Rosalee leaves the house in tears.