As much as he fervently tries to avoid it, Sam has imagined all the different ways it could happen, all of the ways he and Dean could finally give in.
In the end, it’s east bum fuck Utah and a witch.
Source: The Last Shreds of Resistance, by flyingsolo_flyingfree – Supernatural [Archive of Our Own]
Fuck-or-die in the least dub-con-y and (and most hot *g*) way possible.