No, she can't hold back her orgasm

Carrie's breaths come in shaky little gasps as she slowly and carefully walks beside you, as though any step could tip her **** cock over the edge. You're so wet. You can feel the trembling of her body by your side. Her desperation grows with every step until you feel her finally reach a peak. She stops in her tracks, her face one of sheer panic as she realizes what's coming.
"Don't you dare cum," you growl in her ear, your voice thick with lust.

But there's no holding it back. Her face is a perfect mix of mortification and bliss as the first spurt of cum shoots out from under her skirt and hits the pavement. Her breathing is ragged, her face flushed as the floodgates open and a torrent of cum pulses forth, pouring out onto the cement at her feet. It's everywhere. On her thighs, on her shoes. You grin as she whimpers, shaking with pleasure as the bursts of cum dwindle in size.

Nobody seems to notice what's happening, but you still think the two of you had better get out of there before they do. And anyway, the sight of Carrie losing control and ejaculating all over herself has made you too horny to ignore. Before her orgasm has had a chance to subside, you take her hand and pull her into an alleyway, out of sight from the street. You push her up against the wall and get on your knees and start licking the cum off her legs. She gasps and moans as you lick up her cum, gently biting her soft thighs as you kiss them. Standing back up, you kiss her hungrily.
"I can't believe I just did that," Carrie gasps between kisses.
"You couldn't help it," you say, grinning, "your little cock just isn't built to hold back a load."

She giggles as you lean into a deep, passionate kiss. Your hands roam across over her body, caressing and squeezing her curves. You grind the hard bulge of your dildo against her, and she reaches down, running her hand along its length. You unzip your pants and pull it out, spitting on your hand and jerking the dildo a bit, adjusting it so that the base is over your clit.
"I want you inside me," Carrie breathes.
"Turn around," you tell her. She complies, and you lift her skirt as she faces the wall, presenting her ass to you. You spit onto your fingers again, this time applying it to her asshole. You grab the head of your strap-on and guide it to her entrance, pushing the head slowly in.

She moans as you start thrusting into her. The angle and motion as you fuck her lets the base of the dildo rub against your swollen t-dick, and you can't help but let out a low moan. You thrust quickly, eager to get as much friction as you can. You wrap your arms around her from behind as you thrust into her. Both of you are panting, trying not to make too much noise but not really caring. You thrust deep and rock your hips back and forth, and within a few minutes you're grunting as the friction of the dildo base against your clit gets you close.
"I'm about to cum," you pant in her ear.
"Cum in me," she gasps.
You thrust deep and rock your hips to get the pressure you need to cum. You moan and squeeze Carrie close to you as your clit spasms wildly, your orgasm radiating out through your body. To your surprise, Carrie lets out a yelp.
"Fuck! I'm gonna-" she squeaks. This catches you off guard, but you manage to reach around to her cock in time to feel it begin to throb in your hand as Carrie cums again. You jerk her little cock, milking it of what little cum it had left after she came on the street just a few minutes ago.

As the both of you come down from your orgasms, you pull out, wiping your dildo off with a tissue from your pocket and stuffing its length back into your pants.
"Holy shit," Carrie pants.
"I can't believe you had any cum left in you," you say incredulously, "you'd already cum so much on the street."
"I usually have a pretty short refractory period, but it surprised me too," Carrie informs you, "I didn't think I was actually going to cum until the last moment."
"And what about earlier, on the street?" you ask, leaning against her, "How long did it take for you to realize you weren't going to make it?" Even in the darkness of the alley, you can tell she's blushing.
"I think I knew within a few seconds of us leaving the museum," she confesses, "but I refused to fully believe it right up until the moment I started to cum."
"You're so fucking cute," you smile, remembering the look on her face as she realized she was definitely going to cum on the middle of the pavement. You kiss her again, and she giggles.

"So," she says suggestively, "What now?"