Oh, I'm imagining Cas as the figure of a tragic prostitute, waiting deep into the night for his lover to run away with him, dressed in a dark red velvet coat, a gift from Dean he reluctantly accepted back when he still wouldn't accept Dean's declarations of true love and wanting to make his life with him, now a symbol of his resolve; and his face pale with lack of sleep and fear, because Dean was supposed to meet him hours ago and there's a killer lurking around London's underbelly. (1)
But he’s made his choice and he’ll wait forever if he has to. Now that he’s had a taste of happiness, going back to his endless parade of loveless lovers would be a fate worth than death.
He doesn’t know that Dean, a man-of-letter who was sent to London to put a stop to the murderous spree of a crazed were, found himself face-to-face with it at the worst moment possible, as he was, drunk on love and giddy on dreamed tomorrows, on his way to Cas !
Now there are 2 options :
Either Dean’s a werewolf man-of-letter and arrives in torn, bloody clothes, and frightens Cas half to death but consoles him with a kiss and a promise to explain everything;
OR human Dean is left for dead on the streets and, on Cas’s side, when morning comes, a friend finds him on his street corner and brings him back to his home, sick from something undefinable, that only gets worse when they read in a newspaper of the death & burial of one Mr W.
Until a few weeks later, on the next full moon, when a dishevelled man of poor appearance and with fever-bright eyes forces his way to the door of Castiel’s small room ; at first Cas thinks he’s gone mad… (tw for temporary character death!! sorry, I forgot to put it in the right place)
*makes grabby hands for Victorian Melodrama* Both options sound so good, but my evil heart goes for the temporary character death, where Dean returns to Cas and shares the bite with him to make sure they can stay together forever.