As the workout winds down, you warm up.

As the cool down walk continues, the arousal increases. Absentmindedly, your hands go to your breasts. Feeling your huge juggs causes you to catch your breath as you realize how pleasurable it is. You can't believe that you are touching and feeling your own breasts. It's making you even more horny just thinking about the huge tits you now have.

The timer shows 30 seconds left for the cool down walk and you can't wait to get out of here as you don't like the fact that you are liking this.

The man at the front window is still massaging his dick through his pants as he stares at you fondling your jumbo tits. A thought crosses your mind ever so briefly, that scares you and thrills you at the same time.

"I wonder what his cock looks like"

You don't know why you thought that, and you try to avoid thinking about it again.

The tread mill comes to a stop and as you start to get off, the young man outside the window starts to get off. You see him rubbing vigorously and it turns you on like nothing you've ever felt before.

You reach down with one hand and feel the camel toe of your damp red spandex shorts and start rubbing, almost mocking him, teasing him. Your other hand continues to rub your breasts, alternating between the two, and occasionally tweaking a nipple.

He spits on his hand and shoves it down his shorts and starts jacking off in earnest.

You can't believe that he's jacking off in public, that he's jacking off in front of you, and that you are loving it and wishing it was more than mutual masturbation.

You can feel something building inside, something familiar, yet new.

You continue rubbing harder and faster, trying to get as much pleasure from your little clitty nub as you can through the spandex.

The feeling is growing stronger. High pitched moans start to escape your lips.

He's jacking himself faster.

An image pops into your head of you in your sister's well endowed body riding on top of his body with his cock buried deep inside of you. You can envision riding him and making him cum inside of you.

And that's when it happens.

As soon as you imagined his cum entering your body, an earth shattering feeling overcomes you. You begin to shudder as you experience a female orgasm for the first time.

Moans of pleasure uncontrollably burst forth from your mouth. Your hand is squeezing your breasts while the other is feverously rubbing your clit. Instead of the pulsing sensation of cum shooting through your cock, undulating waves of pleasure expand and contract your vaginal muscles like waves washing on a beach. Pleasure building upon pleasure as small orgasms build to bigger orgasms.

You can see that he is cumming as his eyes are rolled back into his head and he's jacking furiously in his shorts. A small dark spot appears on his shorts, he looks at you embarrassed and runs off.

Meanwhile, your rubbing has continued and you can feel the moisture on your hand now as the red spandex of your running shorts have been completely soaked with your juices.

Your pussy juices.

That realization triggers another orgasm, and this one is more powerful than the first. You let out a loud scream of pleasure uttering expletive after expletive, grateful that Sara had CARA soundproof the house. Your rubbing starts to slow down, almost like the cool down mode of the tread mill and your orgasms subside slowly, but a lingering pleasure hangs just out of reach and a feeling of contentment overcomes you.

"Oh MY GOD, that was good" you shout aloud.

You hear CARA's voice again stating...