@moosewithalaptop Castiel had gone undercover as a college freshman when Sam Winchester left his family. He was tasked with keeping an eye on all the Winchesters, but with Sam separated, he had to focus most of his time on the youngest of the three men. The other angels in his garrison could cover Dean and John for Castiel while he was away. Unfortunately, this meant that the others in his garrison had to periodically visit and update Castiel on what was going on. The angel thought he had found the perfect solution for this by introducing them all as his brothers and sisters. No one questioned it when a sibling visited. Especially when they mostly kept to themselves. The latest visitor was Balthazar. He was one of Castiel's favorite brothers, but also the most exasperating. Castiel led him out, embracing him warmly, before turning to see Sam watching him from his desk. Castiel tilted his head. "Is something wrong, Sam? I know Balthazar can be...unpleasantly garish, but I hope he didn't offend you." Castiel was used to Balthazar, so his rampant sexuality and iniquity didn't bother him anymore. That was the only explanation for the look on Sam's face, though, at least that Castiel could think of.