I don't know what happened to my bookmarks, please help me find this fic! It was only one chapter and never updated, but it was a decent size. Castiel and Gabriel are angels, but Dean isn't involved in the supernatural at all. Gabriel hires Dean to act as dominant for Cas, and when he's telling Cas about the present beforehand Cas says something about it being a 'him' and Gabriel gives him a look and says, "Don't even. You are so gay."

Dean is a professional dominant and when Gabriel contacts him by email saying (Kali?) recommended him, he's got a sore throat from the night before and is reluctant, but the one who recommended helped him learn about BDSM, stay safe, and was a great dom, so Dean accepts and asks Gabriel to tell his client to bring a change of clothes. Gabriel brings Cas and leaves him at Dean's house. Cas can see Dean's soul and is surprised that instead of a nest of debauchery this is a 'genuinely good, pure soul'. Dean and Cas sit at the kitchen table and Dean explains safe, sane, consensual and goes over the list of kinks with him. Cas had to ask more to be explained and why it would appeal than Dean was used to, but he was patient. Was safeword 'apple pie' or something like that? After, they went downstairs to start and Cas could see Dean's gold soul change with auburn tones of passion as they started.

Dean blindfolded Cas, but Cas can still see souls with his angelic vision and also chose how to feel through his vessel when Dean started warming him up with something (maybe a cane while Cas laid on a bench?) Dean remarked on how Cas went down so easily, because his trust and naturally obedient body language and no self-consciousness about stripping. At one point, watching his soul, Cas wondered why humanity's destruction had to come about with good people there, Dean noticed his distraction, and Cas said there was something unpleasant at work he was being forced to do, so Dean told him he'd be putting that out of his mind in the scene and let him take care of it. Dean looked at Cas' vessel and would have considered him an officeworker who ran to stay in shape from the muscle on his legs, but the stillness and deliberate way Cas moved made him feel like there was something else. Dean is glad he chose to accept the client because Cas is so open and he wouldn't want him to be hurt/ruined for BDSM if his first exposure to it was with an unworthy, careless dom.

Thanks so much for any help!

EDIT: Found on my own; if anyone is interested the fic is An Angel's Salvation by TokiMirage. Link on AO3: http://archiveofourown.org/works/627676/chapters/1134206