Cas hadn't checked in for a long while, and to say it was worrying Dean would be an understatement. Sam was pissed at him, Kevin was dead, and his mom was none too pleased either. With Crowley still in the wind, Cas was potentially the last person Dean had who probably didn't want his head on a platter.
It made the choice to call the fallen angel a lot more easier when his thoughts spiraled like this. A bit of whiskey didn't hurt either.
"Cas? Uh, this is Dean..."










