Schoolboys have such a vivid imagination when it comes to sex. My most lasting cinematic memory, from days of afternoon truancy to the local cinema, is hunky Burt Lancaster and demure Deborah Kerr, cavorting on the water's edge in From Here to Eternity. ("Nobody ever kissed me the way you did.")

In our boarding school's dormitory, we would endlessly discuss what happened next when, for propriety's sake, the Hays Office demanded that the torrid beach scene be faded from the screen.

"Well I reckon old Burt definitely did her," came a confident voice from the corner. "You could see his boner under his swimming trunks. Bet he came a big load." This was greeted with a universal "Whoah!"

Earlier this year, I recalled that sexy beach scene, while holidaying on Spain's Costa del Sol. I had rented a small apartment near a quiet beach and was getting down to working on the first draft of my second novel. Daily distractions from my writing routine were usually coffees in the bar below the apartment block in the morning or lunchtime Cuba Libres on the terrace of the little beach bar.

The gamine waitress who always served me was certainly not in sultry Miss Kerr's class, but she made a trim figure in her faded blue denim shorts, with long, beautifully tanned legs.

One afternoon, emboldened by two Cuba Libres, I asked her, as she set my third drink down in front of me: "Is your tan all over?"

"For sure!"

"Where do you sunbathe - on your balcony?"

"No, senor. On the naturist beach in the next bay."

"The next bay, you say?"

"For sure, senor. Just three hundred metres away." She cocked her head knowingly, to indicate the direction.

"Hey, I might give it a try this afternoon."

She gave a wry smile. "You will like it, I know. Much fun happens there most afternoons." She idly wiped the table top, clearly willing to prolong our chat.

"Fun?"

"Naughty things."

"Really? Between couples?"

"For sure. Often they don't mind if people watch. Girl-on-girl action sometimes. And of course, many men playing together."

Being bi-curious, the latter category of beach activity immediately caught my attention and I resolved to stroll along to see if I could find some action. I can be easily distracted from work if sex is on the agenda.

My waitress smiled knowingly at me as, half-an-hour later, I left the terrace. "Hasta la vista, senor."

It was a blisteringly hot afternoon. The sort you often encounter on the Spanish costas in mid-September. The golden sands were shimmering in the heat haze and, as far I could discern, there were precious few shady spots. A handful of middle-aged naturists, wearing broad-brimmed sun hats, were walking disconsolately up and down along the shoreline. 'No sign of hot action at this hour,' I thought.

Under a small stand of conifers, I dumped my bag and stripped off. Should I sunbathe or go for a swim? The decision was made for me when who should I see ambling down the path to the beach, but my lovely bar waitress. Now topless, all she was wearing was her faded blue shorts. Her long tanned legs looked more appealing than ever.

She glanced across at the shade being offered by the pines and headed my way. To my alarm, I realised that I was growing an erection. I looked down at my abandoned shorts, but it was too late to retrieve them. She was now close by and clearly amused by my condition.

"Oh my, so have you been having naughty games with someone already?" she asked with that adorable grin.

Like Adam in the Garden of Eden, I forlornly placed my hands over my private parts.

"Er no. As a matter of fact, I've only just got here. I guess it's the sight of your gorgeous legs that's made me like this..." the sentence tailed off as I looked down shamefacedly at my half-concealed erection.

"Mmmm. Did I do that?"

"Seems so."

"I am very flattered." She stroked a hand sensuously across her breasts, making her dark brown nipples stand out tautly. "Why not show it to me?"

Cautiously, I removed my hands to reveal my semi-erection. Without thinking, I stroked my foreskin a few times to get myself really hard for her.

"Oh my, what a lovely cock you have, senor. I would so like to suck it for you."

"You would?"

"For sure. Cock-sucking is one of my specialities. I have many men friends who like me to suck them. And when I am finished, perhaps you will oblige me?"

So saying, she dropped daintily onto her knees - almost like a church supplicant - and began tenderly cradling my cock between her hands. She looked up, smiled, and then started her ministrations, which I have to confess, were truly sensational.

It was a slow, languorous process, performed by a true professional. Shaft licking, ball sucking, deep throating, penis tip tongue-tickling. I was given the full treatment. Soon I was secreting large amounts of pre-cum, which she either licked and swallowed, or smeared over her lips and cheeks. Tenderly fingering my tightening balls she whispered: "Don't cum yet, darling. This is so good!"

I held back for as long as I could, but to no avail. I needed to cum. To fill her beautiful mouth to overflowing with my semen. To see it running down her face and over her breasts.

Sensing my anxiety, she said: "OK baby - now fuck my mouth. Fuck your new dirty bitch whore!"

Her lips and tongue and throat together produced the most explosive orgasm I can ever remember and I screamed with delight as I ejaculated in her and over her. Spunk covered her cheeks and ran down over her breasts.

Quietly she arose from her kneeling position, bent forward and gave me a long, spunk-flavoured kiss. "Now it's your turn," she said provocatively.

I tried to gather myself together, but my heart was palpitating after the orgasm. "Of course, sweetheart. And what would you like me to do to please you?"

She nonchalantly unbuttoned her denim shorts and let them fall onto the sand, revealing the most enormous cock I have ever seen at close quarters. Uncut with a massive hood, all of nine inches long and with the thickest of shafts, it was truly a monster.

Back came that mischievous smile. "Now you suck me. OK?"