Fuck his ass

Letting go of his cock, you take your own dick in hand and give the shaft a few quick strokes, bringing yourself to full erection. Your rod darkens and the round head looks like a plum as it slides out of the receding foreskin, the knob already shiny with your own precum. As you pump yourself, a burst of thick, clear fluid dribbles from your slit and you catch it in your other hand, using it to slick your shaft. Demons produce copious amounts of precum when aroused, as another natural lubricant. You truly are a perfect fucking machine.

Rising up on your knees, you position your cockhead at his entrance, rubbing the knob against his hungry asshole. He makes a breathless noise of mingled need and fear, and you tease him again, rubbing, pressing, grinding the head of your cock against his pucker, starting to spread that ring of muscle and then pulling back. You give your cock another stroke, spurting precum onto his dark entrance, and push against his hole once more, but this time, you don't pull back. You slide past his tight ring with a faint pop and he gasps, his muscles clenching around you.

"Oh! Oh, I feel it," he breathes. "I can feel you inside me." It feels amazing inside his ass, so hot and tight, and you stay there for a moment, just savoring the sensation.

"Wait until I'm balls-deep and then tell me how it feels," you chuckle, taking up a slow, rocking rhythm, pushing in, pulling out, sliding a little deeper each time. His asshole grips your shaft with each thrust and your sensitive cockhead rubs against the fleshy walls of his passage, milking precum from your cock until he's as wet and slick as any woman's pussy. You guide yourself with one hand, watching your meat sink deeper and deeper into your Master's body, until you thrust your hips forward, sheathing your cock to the hilt. You stop, leaning over him, reaching around him, and grabbing his rock-hard cock in your hand.

"You have a demon's cock buried in your ass, and you're still this hard," you say, forcing a wordless whimper from his lips as you stroke him. "You're either gay, or just like being fucked by a demon. Which is it, master?"

When he doesn't answer, you wrap your hand around his tender knob and rub it hard and fast, making him buck and try to pull away, but all that does is push his ass more firmly against your crotch. You grind your hips against his ass, and from the way his body jerks, you've found his prostate. You do it again, and again, and he cries out, overwhelmed by the pleasure, but not yet ready to cum.

"I asked you a question," you say. "Which is it?"

"I- I like being fucked by a demon!" he shouts, writhing beneath you. "Please! It's too much!"

You slide your hand back to his shaft, giving him a slow stroke now and then as you begin to fuck him in earnest, drawing out and thrusting back in, aiming your strokes to hit his sweet spot. He's shaking after your earlier treatment, but soon begins to rock back to meet you, moaning and gasping, the slap, slap, slap of your bodies colliding filling the forest clearing.

Suddenly, his cock jerks in your hand and his asshole clenches around you. "Oh! Oh, fuck, I'm cumming!" he shouts, bucking into your hand as his nuts contract. You grab his cockhead again, warm strings of jizz filling your palm and dripping between your fingers. A heady rush of sexual energy floods through you, filling your body. You feel stronger, your body slightly larger. Even your cock feels a little bigger, but if it is, he doesn't seem to notice. You keep fucking him, harder and faster, milking every last shudder of pleasure from his sweaty, shaking body. Finally, he collapses on the cloak, spent and exhausted, his cock softening and slipping from your grasp. You pull your cock, still hard and ready, out of him with an audible pop. You sit back and lick the cum from your fingers as you regard the dazed and gasping human before you.

Such fragile things, so easily worn out. It'll be an hour before he's 'up' to fucking again. Well, maybe a half hour. He's young. But still, it means waiting, and you hate waiting. You feel the power surging through you, and you want more. With this power, you can change your body to make you more effective at pleasing your partner. Bigger cock, longer tongue, a more dexterous tail...your predecessors have tried them all, and you smile at their memories, the successes and the failures. Then a memory really catches your interest, about chemically altering your body to produce pheromones that increase the human libido, making them horny and virtually insatiable, capable of fucking for hours and cumming repeatedly. Sounds like exactly what you need.

But to do that, you'll need more energy.