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operant conditioning (reinforcement)

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His ass really is perfect, though Grindelwald won't say that out loud -- not now, not yet, not until Graves absolutely needs to hear it. He rubs his thumb around the furled rim and presses his mouth against it with a hot sigh, tugging the man open so that he can tease his tongue inside. Graves' response is gratifyingly swift -- a hitch in his hips, that distressed helpless moan, the sweet clutch of his fingers in Grindelwald's hair.

Graves is so eager, but Grindelwald can tell that the pleasure -- and his desire for more -- is unexpected. Every move is twitchy and instinctive. Every noise is short, his throat quick to close down around it. It's truly a wonder, Grindelwald thinks, that no one has ever thought to do this. Graves is such a proud man. Stubbornness is written in every line of his body and every expression on his face. How could anyone look at him and not want to reduce him to a pleading mess?

"Please," Graves says. When Grindelwald looks up, Graves has half his face pressed into the pillow. His cheeks are bright red, flushed almost as deeply as the little hole that keeps begging to be touched. "Please--"

Grindelwald grins. "And you said nothing good could ever come from my mouth. You want more?"

Graves bit his lip so hard that it blanched under the pressure, but he nodded nonetheless -- a jerky bob of his head as he looked at Grindelwald. He shivered when Grindelwald pressed his thighs up and hooked his arms behind his knees obligingly so that Grindelwald could dive down to his hole again without worries.

"Sweet boy," Grindelwald praised him, promptly rewarding his obedience by eating him out with abandon.

Percival's enthusiasm, so difficult to entice to the surface, is its own reward.

He makes the most delicious sounds. He curses, thighs trembling, and though his cock is leaking, he clearly doesn't dare let go of his legs in order to touch himself. Grindelwald takes pure advantage of this predicament he's forced upon the other man. He pries apart Graves' cheeks and resolves himself to making Graves scream his name before the night is over.

There is something pure about tasting a man here. Grindelwald loves it. He loves the heat of pressing his mouth against another man's hole, and he loves how unexpected his partners seem to find it. He especially loves being the first -- and he so often is -- or if he isn't the first, he'll at least be the best.

Graves' surrender is inevitable but long in coming. He works Graves' over until the poor man is sweating and begging to come. Grindelwald's jaw aches and his tongue is tired but Graves' begging is worth it. He needs more, Graves says -- more of Grindelwald's tongue, more of his hands, more of everything. It makes Grindelwald feel like a king, like a god -- to be able to debase a man like Graves until he's a quivering mass of need.

He licks his way up Graves' cock -- earning himself a tense shudder and a gasp -- and drops a kiss below Graves' ear. "You said you wanted to come, sweetheart?" Grindelwald asks.

Graves nods. There are tears in his eyes.


"And you know I can give you that?" Grindelwald says.

Graves nods again, after a moment of hesitation. They'll have to work on that until Graves is absolutely certain that his every need can be met at Grindelwald's hands, but that will take time. Being able to admit it in this moment is progress that Grindelwald would be remiss to leave unrewarded.

Grindelwald kisses his shoulder. "Then you know what I want you say, don't you?"

Another, final nod -- this one accompanied by Graves' body trembling beneath him, every muscle gone rigid with anticipation and humiliation.

Grindelwald rubs his fingers against Graves' hole as a gentle reminder of what he wants. It's wet and loose, softened by the long sweeps of his tongue. "Go on, then."

The words are dragged out of Graves' mouth by degrees, roughly. "P-please." he says in a shaky whisper. "Please make... Please make me come..."

Grindelwald raises a brow. Graves grits his teeth.

"Please make me come--," he repeats, smothering the last word into the pillow.

Grindelwald snaps his palm against Graves' ass. "Where I can hear you, sweetheart."

Graves hisses, hips jerking against his hand and cock leaking even more profusely -- eager for the pain as much as the pleasure. "Please," he gasps. "Please, daddy--"

Grindelwald growls. "That's my boy."

Graves' hole is a sweet clutch around his cock when he finally slides in deep. Grindelwald barely has to give the man a moment to adjust. The moment Grindelwald's cock is deep enough to nudge against his prostate, Graves has his head thrown back, mouth open in a wail. His fingers are white-knuckled behind his knees, and his cock -- oh, it's rigid as a pole, primed to pop. Graves' voice cracks when Grindelwald wraps a hand around it and strokes it with a loose grip.

"Daddy--" Graves says, chest heaving with desperate breath. "Fuck, please --"

Graves whines when Grindelwald obligingly tightens his fist into something that's nice to fuck into. He thrusts harder too, laughing breathlessly when Graves writhes. Each pump of his hips drives Graves' cock into the circle of his fingers. Its purpling tip glistens, leaving behind ample amounts of slick, and gliding a thumb over it makes Graves shiver like a lamb.

Grindelwald aches to sink his teeth in, but it's too soon, too soon.... He has to reward Graves first.

"Are you going to come for me, my sweet boy?" Grindelwald croons.

A whimper as Graves nods frantically. "Please, please, daddy... let me come-- ahhh-- "

The way that Graves' body tightens as he fights the urge to come draws a hiss from Grindelwald.

"Go on then," Grindelwald commands in a low voice. "Do it, baby boy. Come for daddy, and if you still need more after that, I promise to eat your sweet little hole again so long as you beg for it nicely."

Graves swears, tossing his head back to the pillows. His face flushes red, his breath goes still, and then he's spilling across Grindelwald's fingers in thick streams. Pleasure floods through Grindelwald like a wave, and he follows Graves with a groan as he empties inside his boy.

Gradually, Graves loosens his grip on his legs and lets them drop around Grindelwald's waist. He keeps moving them a little, sliding his feet over Grindelwald's calves. His fingers tiptoe curiously through his spendings like he's amazed at how much he'd come. When Grindelwald finally withdraws, Graves arches a little, spreading his legs to allow him space, and then he turns onto his belly, looking over his shoulder as he props up his ass like an offering.

Without prompting, Grindelwald rests his hand on Graves' hip, caressing the swell of his ass cheek as he eyes the other man's swollen and gaping entrance. A thick glob of come leaks out and slides down. Grindelwald stretches his jaw and wonders if he can keep his promise after all. He's sure Graves will test him, but first...

"What do you say, sweetheart?"

Graves' pink cheeks darken, but there's not a moment of hesitation. "Please lick my naughty hole, daddy," he says. There's only a little bit of impudence in his tone. Grindelwald will forgive it -- for now -- since Graves is sliding his knees under him and dropping down to his shoulders. A perfect presentation. "Please, daddy."

Grindelwald smiles like a shark. "Of course, baby boy," he says. "You know you can always come to me to see to your needs."