Uncle John agrees to be tour guide, escort and chaperone, as Samuel plays the scene
I return from the bar and the man who's been staring at Samuel since he walked in has made his move. Which was to be expected. Samuel is, after all, 17, cute, slim and surfing that coltishly sexual stage - qualities that rarely go unnoticed in gay clubs, even if the proud possessor seems blithely unaware of the effect he's having. Of course, that's Samuel, through and through. He's always been modest, almost insecure. Even as an infant. I remember it well. He'd hide his fat little face behind fat little hands, squirm like an escape artist if you paid the slightest heed to his presence. You could hardly hold ...

Drifting away there ... Anyway, I hang back, observe the apparent conversation, which, at second glance, appears to be a monologue of sorts, the older man - he's 24, at a guess - talking very intently, and Samuel listening, nodding slowly but blinking fast. A sure sign, I know, that he's uncomfortable, nervous, being polite, probably. I should intervene. I don't. Instead I watch. Wait.

Samuel clocks me, waves what is still vestigially a child's wave, open and eager: "Uncle John!" I mime uninterrupted motion, pass the beer, execute a mock-cringe: "Uncle John? Turn it into a rap song, why don't you?" It's meant to be a quip, but it arrives wrecked, cutting edges exposed. Samuel colours; a study in scarlet.

The stranger rescues the moment: "Hello, I'm Ed." Handshakes. "And I'm Uncle John." Pause. "Are you really Samuel's uncle?" I sense subtext, and lie: "Yes. I'm really Samuel's uncle." It's not a dramatic departure from truth. Samuel is my godson, one of my first, and ever since he could talk I've been Uncle John. Ed is suitably impressed. "And is this really Samuel's first time at a gay club?"

I teeter on the verge of self-defence. Of nearly explaining how Samuel told all over a Chinese takeaway. How I reassured him that his parents would weather the news. That, actually, Miriam and Arnold's sole concern would be his peace of mind. (That, indeed, Miriam would probably throw a gay bar mitzvah, rejoicing in the knowledge that her first born would never marry outside the faith.) And how, at some turn in the urgent talk, I agreed to be tour guide, escort and chaperone, recalling, with unbidden clarity, that someone had once done me the same service, staying close, staying on until the combustible blend of thrill, fear and pent-up desire burnt out, leaving only the dumb reality of the routine, and of unspoken rules of engagement, rules that repelled and attracted, amused and appalled: an evolutionary recognition that hard, handsome faces went with hard, handsome bodies, and that eyes you dreamt of drowning in could also coolly appraise, look up and down, and often right through.

"Where are the toilets?" Samuel asks. I point. The escape artist takes off. Ed watches him bob away. As do several others. Ed talks man- to-man: "What you're doing is great." "What's great?" "Bringing Samuel here. He's nice." "He is nice, but it's not great. It's necessary." Ed is blank. "I mean this is the famous phase we go through."

I nod towards the bar, where men in denim tight enough to take their blood pressure slouch around in sultry poses, in studied casualness, thumbs tucked in front pockets, groins thrust slightly forward: the triumph of the willie. And try as I might, I can't do what I had wished, which is to see the spectacle anew, through Samuel's avid inexperience. A return to the long-gone era when I foolishly thought that certain models simply came equipped with added extras - toned, pumped torsos, pearly white teeth, hair that did not dare misbehave, skin that prettily declined to wrinkle - not grasping that the environment, the same old scene, dictated appearance, demanded that you become your own, permanent, ongoing project if you were to compete.

And you did compete, because the pubs, clubs and backrooms were addictive for a time, and, occasionally, for a lifetime.The survival of the identical, except, on intimate examination, they weren't one for all. The sweet, splendid joke was finding media moguls and gas fitters and MPs and sewage workers - same difference - lurking under the same body armour. Meeting and, who knows, making friends with people you could never have established contact with under any other circumstances, class, money and geography presenting insurmountable obstacles. Attention, over there: the mechanic whose bloke is a baronet, his belonging recommended by his beauty; a perishable commodity, of course, but beauty, like money, is there to be spent. That was the mystery of it. What caused you to visit the well, until there was nothing left to draw, not from others, not from yourself, and you did whatever, or who, came after the formative.

Samuel dashes over, breathless, jittery. Ed is concerned, maybe: "What happened?" It takes a while: "In the toilets, at the ... what are they called?" "Urinals?" I suggest. "At the urinals. I was taking a piss and that guy" - Samuel forgets it's rude to point - "stood beside me and kept looking at my ..." I break in: "Oh, that. We get the picture." Ed grins. Samuel bridles: "What's funny?" Ed explains, gently but firmly: "Samuel, it kind of comes with the territory." Samuel turns to me, not entirely convinced. I nod. And he's instantly seven, not 17: "You could have said." "You're right. But there's what can be explained and then there's what you learn. Toilet etiquette you learn." Samuel demurs with absolute certainty, an echo from the past: "I intend to stare straight ahead." I press his cowlick, a habit endured with due dignity: "Your Uncle John is pleased to know it"