I'm kicking down your door to ask about the Ghost/Soap wip!
I'm looking at the remnants of my door and stepping right over them to tell you: I HAVE HAD THIS IDEA FOR YEARSSSSS.
I really fucking want to actually write it, but essentially, Ghost (big bad Ghost!) goes into rut, and one of his worst symptoms is needing to bite (sore gums, instinct to sink his teeth in everything), and Soap shows up at his flat because they made a drunken promise to be there for each other next rut/heat (because it sucks doing it alone), and Soap quickly realizes that Ghost is actually the sweetest fucking thing when in rut. Unlike other alphas that go crazy dominant, imposing themselves on omegas, Ghost wants to be told what to do, and Soap immediately catches onto that and takes the reins.
Of course, what follows is them increasingly taking risks while fucking. They know they absolutely cannot bond (they'd lose their careers), but man, the thrill of Soap taking off his bite guard collar and telling Ghost he cannot bite? Making Ghost put his mouth on Soap but telling him he can't close his jaw? Soap keeps pushing the limits to see how far they can go, and Ghost is such a good boy, doing what he's told even though it's so fucking hard. Ghost gets off on following Soap's orders, and Soap gets off on the sadism/dominance.
Outside of their fucking, they're still CO and Sarg, and life goes on as normal, but in bed, they're freaky as shit.
And naturally, one night, Soap pushes too hard, and they both have to work through a shattered limit they didn't know existed.