What I remember is they are in an established relationship, and the fic is set after a hunt when they get back to their motel room, doused in sex pollen or some sex curse. They have marathon sex with exclusively bottom!Dean. I think at one point one of them pisses himself because he has to go but doesn't want to stop sex?

I've been looking for it on and off for ages, and I just can't find it. Any help will be appreciated.