|Dates||???? - 2013 (killed by Castiel)|
|Episode(s)||9.09 Holy Terror|
Theo was an angel who fell to Earth, and aligned himself with Malachi's faction of angels.
When Malachi captured Castiel, Theo was assigned to torture him, but attempted to question Castiel when they were alone about the possibility of Castiel making contact with Metatron as Theo wished to serve him. Having tricked Theo into releasing him, Castiel slit Theo's throat with an angel blade and takes his grace, restoring Castiel's angel abilities. and subsequently leads to Theo's death.