Yep

"I'm almost there! Get down on your knees" you tell Amber, as you quickly pull out of the teenager's hot pussy.

"What? Why?" Amber asks, confused, as she sits up slightly.

"Because I'm really close! I'm supposed to cum in your mouth, right? Do you want me to waste a perfectly good load of cum?" you ask, suddenly wondering if you misunderstood your assignment.

"Of course not!" Amber says, annoyed, as she gets off the dental chair to drop down on her knees in front of you. She opens her mouth wide, and you quickly slip your wet dick between her bright red lips.

Her eyes flicker up at you, as she waits expectantly. After a few agonizing seconds where nothing happens, she pulls her head back, making your tip slip out of her mouth, though she raises up her hand to catch your heavy cockhead in her hand. "Well?" she asks, demandingly, "Are you going to cum or not?"

"I'm... a little new to this", you admit, "When I took this job I didn't know I was expected to cum on demand. I need a bit of stimulation to reach my climax. Maybe you could help me a tiny bit, just this one time?" You plead, feeling a little embarrassed to have to ask your patient for help with her own treatment.

Amber rolls her eyes at you. "Ugh. Fine! But only because I have an appointment. So, how can we hurry this up?" she asks, as she crosses her arms under her breasts and arches an eyebrow as she looks up at you, expectantly.