For this reason, the names I give are false. I would normally have no qualms about embarrassing the other person – whom I still believe was more at fault – but I understand that if I were to use her real name, the event could be traced to me as well. Therefore I will refer to her as Shelly, and myself as Greg.

We were students at X University, and it was the summer term of the first year, which would have made us both nineteen. After the incident I was given an immediate transfer to Y University, and able to continue my studies with no questions asked. Both universities cited “personal reasons” for the transfer, which was true enough. The only condition X University made for releasing me was that Shelly and I must pay for the tennis court net to be replaced. She didn’t agree, so I paid her share as well, just to be able to get away.

I fancied Shelly like mad. She was extremely pretty and had a fabulous figure. True, she was a terrible flirt, and older men warned me to be careful. But at nineteen, you see shapely legs, narrow waist, full breasts and round buttocks; and devil a thought do you give to any (lack of) morals or kindness she might have.

One day, the conversation turned to tennis. I was quite a good player, and it turned out she liked a game too. At last, here was a chance to get her to myself! We arranged to have a game in the university’s court in a few days’ time, and I couldn’t sleep for thinking about it beforehand.

You should have seen her! She wore the skimpiest of outfits, that vaguely suggested tennis, but shouted seduction. The leotard just about covered up what it was intended to do, while accentuating her shapes and proportions. And she would keep bending down to fiddle with things like shoe straps, exaggerating her movements so that her bottom swayed and swung bewitchingly. I still don’t know if she meant to put me off my game, or if she just liked teasing men.

If it was done to distract me, she needn’t have bothered, because she was a better player than I was anyway. She was surprisingly strong, which oddly I found just as stimulating as her teasing. She served first, and opened the game with a stinger of a delivery that landed beyond my reach. I retreated a few paces, so she sent the next one over short. I got to it and spooned it back over the net; but she belted it into my court, and I had no chance to respond.

When it was my turn to serve, I restored a bit of pride, but she made me work for it. She contested every point, jumping to get anything high and running for anything wide. When she got to the ball, she would send it back to me like a rocket. I found myself thinking about her strength, wondering what it must be like to experience sexually, and suspecting that she liked to dominate. Then I’d miss the ball.

After my respectable round of serving, it all went downhill for me. She had me panting, gasping and sweating, which she found hilarious. To make matters worse a group of her friends, all girls, turned up to watch the last few minutes outside the court. Naturally they all cheered her on, and one of them came up with a term like “groggy Greg” to refer to my real name. Oh, what a hoot! That was so funny, they all declared.

As you can tell, it put me in a bad mood. To make matters worse, when Shelly had one point left to win the match, I slid on the grass. I went down, to laughter and cheers from her friends, and her victory shot landed next to me. She rested her hands on the net and looked down at me (giving me a fine glimpse of her deep cleavage), unable quite to hide the smirk on her face, as she said:

“I hope it wasn’t too humiliating for you to get beaten by a girl.”

To this day I regret my response. I flung my racquet at her. I don’t think it hurt her, but that’s not the point. She vaulted over the net, a picture of fury, and launched herself at me before I had managed to get up.

She grabbed my shirt with one hand, while the other she clenched into a fist, which thundered into my jaw. After seeing the way she played tennis, it was no surprise that she hit hard, and my jaw throbbed and stung. Then she hauled me up to my knees, ripped my shirt off me, and – to roars of delight from the girls – tugged my shorts off for good measure.

It has always excited me when a woman takes the initiative. As I’ve already said, her dominance at tennis was arousing enough; but what with her leaping over the net, punching me, and then tearing my clothes off, I had an erection. She pointed at it while I stood up, and declared loudly for her friends to hear:

“I thought you were perving over me, and I was right, wasn’t I? You’re a dirty little boy who hasn’t grown up yet! You’re also a coward who’s scared of fighting a girl, so you throw things at her instead!”

“Hit him again, Shelly!” one of her friends shouted, and she smiled for the first time since the game. She looked at me and murmured quietly, so her friends wouldn’t hear:

“All in good time. Your serve, I think.”

Well, I’d got myself into a dreadful situation, hadn’t I? What was I to do? If I backed down, I’d be the coward who was scared of a girl, that Shelly had described. But if I hit her, what would I be then? Exactly. She could see me weighing it up, so she added helpfully:

“Jane wants me to hit you again. Oh, I’m going to do that, don’t you worry! I’m going to blacken at least one of your eyes, and bruise the rest of your face so badly you’ll be ashamed to look in the mirror. So you might as well take a shot at me now – if you can!”

I lunged with my right; but her fists were up immediately, knocking my arm off course. I stumbled, and she slammed her right fist hard into my kidney. I instinctively reached for the pain - and saw too late a fist coming at my face. That was the black eye taken care of!

I staggered to stop myself from falling; she moved in close, and brought a knee up hard into my balls, at which her friends whooped and cheered. Red hot pain seared my body. I felt sick and dizzy. Then up came her other knee, smacking nauseatingly into my already wounded balls. But through eyes blurred with tears, I could just make out a fist swinging upwards. It caught me plumb under the chin. My teeth clanged together, my feet left the ground, and I landed with a jarring thud on my back.

“Lovely!” shouted a girl’s voice.

“Wish I had a camera!” called out another (luckily there were no mobile phones in those days).

“Get up, you wimp!” yelled a third.

Despite my best efforts, I couldn’t help shedding tears. Shelly stood above me, mocking, and telling me how she’d already given me a black eye, kneed me in the balls, and “decked” me. But she was keen to start fighting again. She stood over me, fists clenched, and goading me to get up.

Impatient to get going again, she seized one of my arms (I can’t remember which) and grabbed my balls with her free hand. Then she hauled me to my knees and dragged me about on the grass, like a dog on a lead, before her fist came down like a club on the arm at its socket. It was useless to me for the next 24 hours.

As soon as she got me to my feet, she was back at me with her fists, first one and then the other, dead straight if I remember rightly. She fought in the same way that she played tennis: sensing an opportunity, anticipating my moves, and striking before I had recovered – hard; very hard.

I must have been retreating, because I felt something against my back. It was the mesh of the enclosure. More people had gathered to watch the “fun”, because I heard male voices as well as the familiar ones of Shelly’s friends. I remember one pointing out that I had an imprint of the mesh on my back and laughing.

The enclosure absorbed me before throwing me back again, and sure enough she was waiting for me. It’s strange the things you remember, and in my dreamy state I thought “That’s her left fist. It won’t be as bad.” Whatever, it had me back where I had been, and the mesh rattled and echoed as I bounced into it. She didn’t wait for it to spring me back this time, but caught me another one under the chin. The back of my head bounced against the mesh, rather like the tennis ball had done against the racquets a matter of happier minutes earlier.

Bang! Her fist homed round in a hook, catching me severely on my ear. My hearing went all distant and foggy, and stayed that way for about as long as it took for me to be able to use my arm again. I found myself lurching to one side, but she had me upright again with another of those powerful uppercuts.

In my near-hallucinating state, I thought one more punch should do it. Please get it over with, I thought, then we can all go home to safety, and I can forget about this nightmare. Sure enough, the smiling young woman drew her right fist back, and held my chin steady with her other hand. Her fist came up and under my chin one last time.

I wasn’t quite unconscious, but my thoughts were nowhere near ordered, and it’s the closest I’ve ever been to dreaming while still technically awake. I seemed to drift. In fact, it wasn’t unpleasant, and there was no pain. (That came later.) I appeared, to me, to sail slowly down onto my back. Then she was on me, and reality came storming back.

Now, I’ve already written that I found her strength stimulating when we played tennis. Despite the damage she inflicted on me, her fighting skills aroused me as well – more so in fact. Every time she punched me, a message was sent to my brain, and a little extra blood found its way to my most sensitive spot. Now she was sitting on it.

She knew exactly what she was doing, too. As she swung a punch into the side of my face, she stirred that delectable bottom against my groin. She hit me with the other fist, and ground harder. She was going to have to stop soon, before I disgraced myself even further. But a third punch struck home, she gyrated on my cock … and I shuddered and shouted in orgasm.

Shelly jumped up, and I put my hand over my eyes in shame. When I removed it, I saw she was carrying her racquet most prettily over her shoulder and smiling down at me.

“Well, I’ve never made a man come that way before, and I thought I knew every way there was!” she exclaimed, before blowing me a kiss with her free hand, and then walking away back to her admiring friends; swaying her hips and swinging that naughty bottom.

I have never played tennis since.