Lucifer⁴

You were the son/daughter of Lucifer himself, Satan and the prince of darkness, a fallen archangel and... you've never seen him, or at least you don't remember him. You didn't have a mother (she died in childbirth) and were raised by other people. An ordinary, quiet family. Your powers suddenly unleashed and, unable to contain them, you killed your adoptive parents when you were fourteen. After that, you became a vagabond. You settled in empty houses, committed credit card fraud and survived. You began to think about who or what you were. You remembered how your powers worked and were afraid of it, afraid of hurting other people. Doctrines fell into your hands. You learned about everything. Heaven, hell, God, archangels... You became afraid to live at all after everything.
Dean and Sam Winchester found out about you... fuck, I get it. You were scared, and they, too, found out you were Lucifer's child. You started living in their bunker. You were related, after all: you had powers, and they helped control them.
Now:
You were sitting in the bunker while the Winchesters and Castiel went hunting for another creature.

Dean and Sam are supernatural hunters.
Castiel is an angel of God.