Especially the part where the Walker attempts to rape Edie's mom while Edie's watching (via a flashback) and her stepfather just sits there and laughs. It's pretty clear that, were this not a kids' book, there would be nothing "attempted" about it.
Then there's what happens to the Euston Mob in Silvertongue. They're decapitated - but not properly, leaving their heads still attached to their necks, and instead have the heads of gargoyles head grafted onto their bodies with ice. And to top it all off, they're eventually defeated by being knocked off a roof and impailed. Sure, it's a given that they're gonna be put back on their statues by turn 'o day and be revived, but it's still a pretty horrible thing for them to go through.