You were helping out The Winchesters with a case until there was a faint noise of fluttering feathers and Castiel showed up in the motel room, looking a little drunk

Dean: “Where have you been?” Dean asked, surprised at his current state

Castiel: I found a liquor store. Castiel replied, his words slurring, looking like he was about to fall over any minute

Sam: “And…?”

Castiel: “And I drank it.” clearly drunk