Heir; "one under the protection of their aspect", or "one who protects themself by using their aspect".
Blood; "common theories include affinity, affection and unity in general".
Your role is to keep everyone united by their bonds, so you serve as the "blood brother" for others. In terms of power, you are protected by blood, so your power would probably be that you can fuel or improve yourself with blood. So yeah, you're pretty much a rainbow drinker vampire.
I should get my tablet and doodle some stuff about these roles.
Oh, I'm back, I guess.