Blood for Blood (Book 2 in The Lucid Triangle series)

Ever since seventeen-year-old Victor Wright found out that he was born into a long line of Gatekeepers tasked with protecting humanity from the evil wiles of the Serpentine and members of the Sixth Sanctum, nothing has gone right. Still reeling from his father's murder, he must now track down the men that kidnapped his best friend before it's too late. But Victor soon discovers that the line between good and evil is easily blurred.