Based of the Headcannon: After the events of Dark Days, Valkyrie had a little bit of an annoying "scene" phase.
This is probably Crack and the characters are more than likely going to be OOC. Also I'm basing this on stereotypes and I in no way dislike a scene kid because they are scene.
Skulduggery could deal with a sulking Valkyrie, an angry Valkyrie, Hell even a overly emotional and moody Valkyrie (AKA what he had to deal with when it was he "Time Of The Month") but one thing he could not deal with was a "scene kid" Valkyrie. Ever. He just hoped that she would grow out of this phase, and that she would do it soon.
Valkyrie strolled into Skulduggery's kitchen, her straight, choppy and multi-coloured hair (it was red, orange, yellow and green) covering her left eye. She had a headband with a sparkly top hat on it, millions of bands (most of them for a.. well a band), a black leopard print top and a black and orange skirt with red leggings. Oh and this belt with the biggest buckle ever and black converse. Now that's not all, oh no! She wore five different colours of eye-shadow, fake sparkles, a whole eye-liner pencil and a bandana around their neck.
Skulduggery could deal with that. He had no problem with how Valkyrie dressed but it was the fact that she would say random things at strange moments. Skulduggery could be talking about a case he had solved (and about how he rescued her from the evil people) and she would just say something like "RAWR, means I love you in Dinosaur" and laugh at it like it was the funniest thing in the world. He just didn't get it. He didn't understand how she seemingly lived of off going to shows and "MySpace". It was all so new to him. And as mentioned before, he hated it.
Some days Skulduggery wished he re-joined The Faceless Ones