Castiel shook Heidi's offered hand, glad that the attitudes of some of his brothers weren't being held against him. Especially Uriel. Uriel grated on his nerves as well so he could only imagine how the humans perceived him.
"Curiosity," he answered honestly, a small smile on his face. "I've been in this city for over six months and still haven't ever really met Angel Investigations. I thought it was about time that changed."
He glanced around the lobby, sensing the power in this place. Not merely the super abilities, but power in every sense of the word. They were good people here, each chosen in their own way.
"Given that the Powers That Be work mostly through your people, I decided I really should offer more help to you all."