Set after "Of Course"...

There's a hint of rebellion in Barney's eyes when Marshall slips inside the other man's office the next day. There's a rumble of anger in his voice and a sharp edge of jealousy, like the sounds of an approaching storm. "Why do you do that?" Barney whines. "Why are you encouraging Robin? You're supposed to be my Bro. If you're crushing so hard on Don then why don't you date him?"

Marshall's having none of it, and in two strides he has the other man pinned against the wall by his throat, almost sending one of his motivational posters crashing to the floor. "Shut your mouth," Marshall orders him, fingers scrabbling at Barney's fly, dragging down the zip and pulling at a handful of soft suit-pant until Barney gurgles with anger. "Belt!" Barney chokes. "Belt!"

Marshall shakes himself, sliding a finger under the leather tongue and pulling Barney's belt free of the buckle. He's still ultra-stressed from a morning being balled out by his boss and another attempt at giving up cigarettes and all he wants right now is to hurt someone. This is not the chain of screaming, although sometimes there's plenty of that. This is the chain of pain. He dishes it out, Barney takes it.

"Come on," he demands, his fingers tightening around Barney's throat, pressing into his windpipe. "You're mad at me, why not yell at me some more?" He grins, as Barney goes pale then a little blue and his throat makes a hollow rattling sound.

"Exactly," Marshall says, back-handing Barney across the face. "This isn't about you, dude, and your issues with Robin and Don. This is about me, and Lily and that jerk Scooter. Do you know how mad that Lunch Lady thing makes me? Do you know what I really wanna to do Lil when I think about that bozo's hands on her..."

Barney whimpers as his pants sink down around his hips and Marshall grabs his crotch. Barney shakes his head, blue eyes wide with fear, and Marshall knows he's not begging for himself. He's begging for Lily.

Don't hurt Lily, Barney's saying, silently pleading, the long column of his throat rubbed red raw from being half strangled.

Don't hurt Lily, he's asking, when Marshall squeezes, feeling Barney's soft cock and balls squish slightly in his fingers while he stares at the other man as if daring him to cry out.

But Barney's dick stiffens in his hand, it swells and pulses and Barney makes a little needy noise that means it's okay, he can take it; he can take anything Marshall gives him. "Dude!" He squeaks, and Marshall has to stuff his own tie in his mouth to shut him up.

Later, with Barney bent almost double over his own desk, and Marshall forcing his dick again and again between Barney's tight, gym-toned buttocks, he wonders if any of the women Barney sleeps with ever ask him about the marks? He wonders if Barney ever tries to explain the scratches and the bite marks and the bruises.

But really, when Marshall comes with a sighing spurt, and his mind goes blank and peaceful, he finds that he doesn't really care. Lily's waiting for him at home, and that's all that matters. And now he's pretty sure that Robin and Barney aren't going to get back together and put a stop to his and Barney's games, his wife is safe once more.