Unified
Everyone in your crew comes down the same recognised line. It will back you when it suits it, and it will remember that it did.
YOU ARE WHAT THEY LEFT BEHIND
What you are
Go back far enough through your mother's people, or your father's, and you reach something that was not human.
Your Bloodline is the line you came down: a branch running back through generations to one of the Watchers, who has others besides yours. It was settled before you were born. It is where you came from, not who you choose to become.
Devotion is the part that is yours to decide. You can swear to the Watcher behind your own line, or to a different one, or to Azazel, or to anything else that will take an oath from you and give something back for it.
Unified or Stray
One Watcher stands behind many Bloodlines. Some of those lines were recognised and have kept their own records ever since; others were never recognised and have managed perfectly well without.
Stray
Your lines are different, or nobody ever recognised them. Stray is a description of your paperwork and not of your ability.
What you know
Your Bloodline decides what you can do. Your upbringing decides whether anybody ever told you. Some families teach it from the cradle, and some spend everything they have on making sure the child never finds out.
You can die here.
Sometimes what is in you refuses, at a moment of its own choosing, and takes payment afterwards in a form you were not consulted about.