Good world-building. Derpy characters. Horribly offensive if you're Asatru or a Lokean. Or identify as a gypsy. 
 Also, when listing mythical persons like Valkyries, etc. it's really not OK to throw in things like 'Persians, Celts, and Vikings.' Those people really existed. (And were, for the most part, merchants and traders, not destructive teenagers using their heritage as an excuse to be dicky.) 
 I don't think Gwen is so much stupid as she is lazy. She's so self-absorbed she just doesn't see things when they crack her over the head. It's not that she's dumb. She just uses her smart to do things like start a business, sneak off campus, and pour over comic books. (So much so that I wonder if the author knows much about graphic novel pricing and the fact that Gwen only gets money if she does a job, which she doesn't do very much at all.) 
 I'm convinced Morgan is a virgin. Being the school slut at one time, I'm speaking from experience. Once one guy says it, the rest of them have to follow or they look like they didn't score with the sure-thing-that-wasn't. Doesn't matter if it's true. 
 The thing is, I can't put these books down! It's like crack! I even stopped being pissy about Loki and started laughing. It's like Jesus Christ: Vampire Hunter for pagans. Crack, I tell you! 
 Also, the author needs to get a girlfriend. The whole eating pumpkin thing is unintentionally hilarious. Holy crap! 
 Preston is really clearly a Malfoy, at least to me. Oh, and he's a Death Eater, how surprising. Once I got that into my head I started recognizing a lot of characters were on vacations from their usual series. Nickamedes is Snape. Gwen is straight from Torchwood with Hermione's body. Savannah is Ron. Morgan is Sirius. I'm convinced Logan is James. 
 That being said, if this is the crossover fic I think it is I'm on board. I wave my flag of surrender. The book wins. Dammit! Books come out sooner! Grr!