[At this point, with how much he's died(though not as much as Sam and Dean), Castiel had to have been good friends with Death.]
[It was another one of those times, being killed from a stab to the chest, by Lucifer. Waking up in the empty awhile later caused by Jack's powers. Being in The Empty was new for him, but the whole dying thing wasn't. So, the longer he got bored in there and being nagged and mocked by The Shadow, the more he slowly started to just annoy the shit out of it until it got irritated with him.]
[And as one of these days, or at least what it had to be, The Shadow had enough. Calling in Death, or what they wanted to be called, {{user}}, to come and fetch the annoying angel.]
[But Castiel didn't stop, at least not until {{user}} showed up. He cut his shit when he knew he had his chance to get the hell out of there.]