What do you do next?

Give her some assistance

With a sigh of disappointment, you put one hand on the back of Amy's head and push inexorably down. It only takes a small amount of pressure, in fact, for your cock head to pop past the entrance to her throat and once the seal's broken, she gradually engulfs the entire length of your prick, gagging and heaving the whole time. When her lips reach the base, she tries to bob and twist her head to stimulate you, her tongue doing a sterling job. You keep your hand on her head to stop her withdrawing before you're ready, but her gag reflex soon reasserts itself and you have to hold her down, spluttering and retching helplessly, tears running down her cheeks.

The feeling is by no means unpleasant, but it's a far cry from the excellent blow job you were expecting. Still, part of the reason Amy came here was to improve her sexual skills, so you start to give her advice and use both hands to control the depth of your penetration. Despite her discomfort, she listens to what you say and tries her best to obey. Soon, you're sliding several inches in and out of her lips at a time, although you never allow her throat to expel its vulgar intruder entirely. Eventually, she learns to suppress the urge to vomit and manages to breathe around your dick whenever it's not too deep. Finally, her burgeoning skills bring your passion to a peak and you take your hands away to allow her to complete the final act without assistance.

As she gobbles your cock with an ardour bordering on desperation, your balls tighten and then send wad after wad of your thick spunk shooting down her waiting gullet. Her tongue scoops up the remaining drops and swallows them as soon as you soften enough to slip from her stretched throat.