He has her start blowing him.

David stared at Aza for several moments, and considered her words. "...you really want to?" he asked her.

She nodded fervently. "Yes, Master, I would absolutely love to serve you sexually. I genuinely get off on your pleasure. Genies like me? We love to serve."

He slowly nodded, seeing her eyes, wordlessly pleading with him to let her do something pleasurable for him. "Go ahead," he finally said.

She beamed and with one soft hand, groped him through his pants, before using her other to unzip him, and pulled his member free, taking a moment to gaze at it adoringly. "Beautiful..." she breathed.

"... it's just a penis," he stated sheepishly with a blush.

"It's my Master's penis," she corrected as she gently stroked it with a hand, and extended her tongue to lavish the head with some oral attention. Her pink appendage glided along and over the purplish flesh of his cock's tip.

He moaned as she did this, while she continued to gently jerk him off. "Oh, god, this is amazing..." he panted, before she opened her mouth, placing her hands on the thigh she was leaning over as she lowered her head over his crotch, taking his cock between her lips as she began sucking.

She giggled in a giddy manner as she pulled back up until only his tip remained in her mouth, then lowered her face on his cock again, before rinsing and repeating, bobbing her head on him repeatedly. He bucked his hips into her mouth, and gasped in pleasure. He looked down and met her eyes, which glimmered with delight as she took him to the root, and ran her tongue along the base of his shaft while it was in her mouth.

It wasn't long before his cock swelled with impending release. Her skillful blowjob was too much for him. With a gasp of pleasure, David came, grunting loudly, and letting his salty discharge shoot in short, intense spurts into her mouth. She gulped it down like it was ambrosia, and she murmured around his shaft happily, clearly on cloud nine. She then pulled off, looking at him with doe eyes. "Did I please you, Master?" she purred.

He panted, and could only nod in agreement as she stroked his thigh with a hand.