'Blood Oath is a sequel to Blood Scent. We discover more about the Rogue, Seeker world in Australia. This is the story of Cassie and Matt, based in Tasmania. Matt kills a rogue vampire who wanted Cassie. This sets up a course of events where the rogue’s twin has sworn in a blood oath to avenge his brother’s death. Throw in a bunch of vampire hunters as well and you have trouble. Things become even more complicated when Cassie’s sister is kidnapped as bait. The only option may be that Cassie will have to give up her own life to save them all.'
Source: Publisher's blurb.