I was sure it was just indigestion but the pain in my chest and the sudden eruption of an epic sweat made my colleagues ring an ambulance. The paramedics were there quickly and were sufficiently worried to take me into A&E. Once there I was wheeled into a side room and one of the doctors came to see me. Embarrassingly it turned out to be Jill, a young doctor I saw occasionally at parkrun. She ran with a group of medics that I knew and, despite the fact she often ran with her boyfriend, I couldn’t help but be attracted to her. She was tall. 5’10 at least, two inches taller than me. Short blonde bob haircut, a ready smile and beautiful blue eyes. In summer her t shirt clung to two perfect breasts which I tried not to notice jiggling as she lapped me on the return leg. In the winter her tight leggings only served to show her pert, curved bum and once, when I was stretching with the group I could have sworn I caught a glimpse of a luscious pair of lips, stretched tight under the Lycra. It was an effort to run comfortably that day I can tell you.

“Hello Al, what on earth are you doing here?” she asked, briskly lifting my chart. “A heart attack? Really?”

I blushed and explained that I thought it was more likely the cheese sandwich I’d eaten while running from the train to work.

She grinned.

“Yeah. But better safe than sorry. Let’s run some tests.”

Methodically, she set about taking my pulse—"Bit fast", temperature— "Normal", and listening to my chest—"Fine”. I couldn’t help but notice the way her scrubs pulled tight across her boobs as she leant in. I could clearly see her nipples were standing proud beneath the dark blue. I tried not to look but I couldn’t help it.

“Ok. Last one. Just lie back and I’m going to do an ecg.”

I lay back and tried to ignore the touch of her hands as she expertly attached the pads. One pad skipped off and slid down the side and without think she leaned over me to retrieve it. Her breasts slide across my naked chest and I felt her hard nipples graze my own. I gasped and then blushed a deep red.

"Oops,” she giggled. “now. Stay very still.”

The machine beeped and I tried so hard to ignore my raging erection. I tried even harder to stay still as she absentmindedly reached down and massaged my swollen shaft through my work trousers.

“Mmmm. Seems your circulation is fine anyway.”

The machine whirred and beeped.

I tried to stay still as she undid my belt. Unbuttoned my trousers. Slowly unzipped my fly. Her eyes twinkled as she pushed my underwear aside and freed my now totally hard cock.

I gasped and twitched. The machines alarm went off and she reset it.

“Let’s try again.”

The machine beeped and whirred.

I tried to stay still as she slowly wanked me. Up and down her hand traveled, fingers firmly grasping my hardness. Her other hand cupped her left breast through the tight scrubs. She flicked a thumb over her own nipple and sighed with pleasure. Beneath the material her nipple grew. So did my own arousal.

The machine beeped and whirred.

Jill let go and pulled her scrubs off. She deftly removed her bra, releasing her gorgeous tits and drawing an audible “yess” from me. Her breasts were bigger than I imagined, unconstructed by a sports bra, they were heavy and pendulous, full and weighty but still young and firm. Her hands slid under each breast, gently cupping the low curve before squeezing them together and again flicking her thumbs over the swollen tips. Her beautiful eyes half closed and a sexy gasp escaped her pouting lips. I moved my hand up to take a grasp of my own but the machine alarm went off again.

She reached down, swatting my hand away before resetting the machine.

“Stay. Still.”

I obeyed. My eyes drinking in her wonderful nakedness, even more sexy than I had imagined beneath her running kit.

The machine beeped and whirred.

Looking me in the eye, Jill bent forward over my body. Her tits dangled either side of my cock and she gently opened them in each hand before closing them again, trapping me between the soft flesh. I moaned but stayed as still as possible as I felt her push down, pulling the skin from the throbbing head of my dick and teasing out some of the slick pre cum that had started leaking beneath. The wet feel against her chest illicited another sigh as she began to move.

The machine beeped and whirred.

I lay still. The only part of me moving was my cock. Harder than ever. Trapped between two slowly moving perfect breasts. Listening to Jill’s contented sighs. Her breath slightly faster as her ministrations yielded more slick juices. I could feel my length leak more pre cum, slathering her wonderful frotting orbs. I gasped.

Feeling the inevitable buildup in my loins, a heat and weight building from below. I moaned in warning, making eye contact again as she looked up at me, but her pace never slackened. She was biting her lower lip as she worked me between her tits. Up and down she slid, the sound of the machine joined now by her sighs, my moans and a rhythmic squelching.

I whispered, “I’m gonna cum, Jill,” and she replied, “Yes, you are.” Her grip on my cock became firmer and on each downstroke she paused now, exposing the swollen purple glistening head of my penis between her flesh pointing directly at her opened mouth.

I gasped.

I came.

Hard.

The orgasm built from my ass through my balls and prostate into my dick with such force that the first thick rope of cum shot out across her face. The second splattered against her chin before falling across her fingers, nipples and breasts. The third and fourth pulses were lost between the soft folds of her flesh but I felt my hard heavy cock slide through its own thick, wet mess as she once again pressed me firmly into her cleavage. Gradually, my throbbing and pulsing cock calmed and my breathing returned to normal.

Jill gave a regretful sigh as she gently released me from between her cum covered tits with a sexy wet squelch.

She checked the machine

“Well within normal parameters. I can certainly pass you medically fit for next week’s parkrun,” she blushed, “and, given how you performed, I’d expect a personal best.”

“Now, you do, of course, need to help me out.”

She grasped my hand and peeled down her trousers and knickers revealing her swollen, neatly trimmed sex. Guiding my hand to her sex she gasped as my fingers slid between her heavy set meaty lips and instantly found her engorged clitoris. With one finger either side, I slid them over the swollen nub, gathering juices from her dripping pussy as I did so.

She moaned and leaned down, catching me in a deep probing kiss that swirled tongue and my own cum into my hot, willing mouth. Willingly, I tasted myself on her hot breath, ragged now as my hand worked her sodden, swollen mound.

Jill moaned and broke our kiss as she leaned further forward, bringing her frosted tits to my mouth, pushing the cum spattered orbs into my face. I gladly opened my mouth and began to kiss, lick, flick and suck them, revealing in the taste of my freshly deposited cream and the feel of her hard fat nipples beneath my hungry tongue.

Jill gasped and sighed as each flick of my tongue on the tips of her tits elicited a little pulse and squirt from her sex beneath my fingers, now describing little circles around her pulsing clit. I felt her orgasm build. A hot wave of juice and trembling delicate flesh pulsed in my hand as her breathing grew shallow and tight. A moment later, her thighs clenched, trapping my hand in a throbbing wet triangle of pulsing twitching pleasure. Her low moan filled the room and her body juddered as pure pleasure coursed through her body.

I lay back, in wonder as ever at the power and sensuality of the female orgasm flowing through her veins.

Gradually she subsided and came back to reality. She stood straight, gasping as I planted one last kiss on her now clean breasts. She opened her legs and released my hand, covered in tendrils of her pussy juice.

She looked down at me and giggled.

“I’m not sure that’s a medically sanctioned test for heart conditions,” she laughed, “but it was definitely fun!”