"Some how I think your 'reasoning' isn't what Johanna was used to." He remembered the look on both Dean and Sam's face when he had told him Jo and her mother were dead in their original time line when the whole Titanic debacle happened. He didn't think that Dean would have been so nonchalant about the girl's death. He also realized the fact he felt more about another Jo's death was very indicative of the fact that his time here in Madison changed him. As was his affinity for his niece and a few other people. Damn.
He spread out his hands in front of him. "Alright, you've got me. Cas is here and yes, he is the one keeping my bed warm at night. And I'm sure you won't be surprised in my saying that if you try to hurt him in any way, I will take it upon myself to kill you." And he was serious about that. It might not go over well with Cas or Mary or a lot of other people, but if it meant keeping Cas safe, then he would.
And maybe he was still a little jealous about what had happened back home between the angel and the hunter.