Yes, have some fun with him

The sound of his desperate whinings finally persuade you to let him cum, and you knw exactly how. You place two of your fingers into your mouth, sucking on them and coating them in your own saliva, whilst your other hand pushes his legs apart, exposing his asshole to you. You take your slick fingers out of your mouth, circling them around on his hole, and you hear the demon let out another desperate whining moan. Grasping his precum-wetted cock in your other hand, you rub it gently as you firmly start to push your fingers into his ass. It is smooth and warm, enveloping your fingers and he lets out a little gasping moan as your fingers slide into him until your hand presses against his ass. You grip his cock more firmly, slowly stroking it from base to tip as your fingers rub around inside him, searching for his prostate. It is easy enough to tell when you find it, your fingers rub over a small bulge and the demon's body flexes, several drops of cum being squeeze out of his cock as he moans. You smile to yourself, and begin to make a beckoning mothion with your fingers inside his ass, rubbing them firmly over the spot that is his prostate. His moans become breathy and desperate, and your adjust the motion of your hand to come to a stop just below the head of his cock, stroking it as if you are trying to literally squeeze or maybe even milk his cum out of him. And to a certain extent you are. His legs start to shake and scrabble at the floor, and his back begins to arch as you toy with him. Cum starts to flow from his cock, running over your hand. You stroke him faster, and it start to spurt out, almost splattering your face. You push harder against his prostate, and his whole body spasms in orgasm under you, his cock gushing and squirting cum. You relax your toying with him for a moment, letting him bask in the orgasm, before you redouble your efforts.

You lower your face to his cock, wrapping your lips around his now oh-so-sensitive tip, stroking and milking his shaft and rubbing his prostate with two fingers inside his ass. His cum still streams into your mouth as you swirl your tongue over the tip of his cock, and he moans involuntarily, begging desperately for you to stop. But you keep going, swallowing every droplet of cum you milk out of him, his cock and asshole pulsating and clenching around you as you provide him an unbearable amount of pleasure.

Eventually the flow of his cum stops, his crotch flexing dryly, and you extract your fingers from his ass and slide your body off of his. You stand over him, still clutching his leash and watching him lie dazed with pleasure in a slight puddle of both of your juices.