The late 1990s and early 2000s were a difficult time to be a Prince fan, not just because he was still in the creative gulf separating 1996's botched Emancipation from his return to the mainstream with Musicology in 2004, but because I wasn't even a teenager yet. I'd been given The Hits for my tenth birthday (My Dad was a fan); I played the first track – ‘Soft and Wet’, from his first album, For You (1978), sung in a joyful, sexy squeal – and then played it again and again. Who wouldn’t want to listen to Prince?

My classmates didn’t. They were too young for the internet – too young, probably, to be listening to their parents’ record collections – and, reasonably enough, preferred their ignorance to my proffered revelation. More surprising though, in retrospect, is what they did know about Prince. He was a nobody, a has-been if he ever had-been. There was a humiliating moment when my friend asked every single person in the boys’ changing room who they preferred, Britney Spears or Prince. Britney won every vote. But he was also, and this came up again and again, gay. Definitely gay. He wore high heels, and make up, and had long eyelashes, and he'd taken out a rib so he could suck his own cock, which was really, really gay.

Prince was my discovery, and I saw myself as his last defence. I stalked the corridors, bristling with facts, ready with indignant questions: did you know that he made his first album at 18 and played every instrument (27 of them)? That he wrote all his own songs, produced and arranged them (I barely knew what this meant)? That he had won an Oscar (for Purple Rain)? That he was the first artist to have a number one single, album and film at the same time (in 1984)? That he had recorded the soundtrack for Batman (the highest grossing film of 1989)? That he'd sold over 100 million records? That Eric Clapton said he was the greatest guitarist alive? Had you seen him dance in those heels?

None of it did any good. When you're a child the past is weightless, invisible – it hasn't found its authority yet. But for me, listening to Prince, the past seemed infinitely more exhilarating than the present, and full of strange new things. Through him I looked backwards into the adult world: the dirtiness in his lyrics (‘Soft and Wet’) gradually became legible as new facts were sieved through schoolroom conversation. They gave me a sense of guilty proprietorship, as you have for decoded secrets. It wasn't all titillation: a song like ‘If I was Your Girlfriend’ was clever and bleak and weird, with its repeated, impossible 'if':

If I was your girlfriend, would you remember
To tell me all the things you forgot when I was your man?

If I was your one and only friend
Would you run to me if somebody hurt you even if that somebody was me?

And I looked at him, of course. At the clothes – the sensual thrill of all that shiny silk and frothing lace, the shock of it, cut away against the taut, hairy body. His complete, overriding sexiness was at odds with everything I knew a man was meant to represent, but there it was, all the same, staring you in the face. There came a moment when I was told, yet again, that Prince was gay (he wasn't), and for the first time answered back: 'So what if he is?'

I think now that what I was insisting on was Prince’s authenticity: not only his genius but also his willingness to break rules upheld as rigidly in north-east England in 2000 as they had been in Los Angeles in 1981, when, appearing as the support act for the Rolling Stones in a trench coat and bikini briefs, he was booed off stage. I suppose I was also insisting on some integrity of my own. When the news of his death broke yesterday, I received messages of condolence from friends – as if I were a relative – which made me realise how much I’d used Prince to define who I was.

Seeing him in the flesh was almost too much. I saw him perform in 2007 and 2014, each time with a tightened chest and pricking tears, so that now I can barely remember any of it. The second time, the gig had been announced that same morning, and I queued for six hours in the shallow February sunshine, thousands of people beaded down residential Camden streets. We swapped beers and stories; someone with a ghettoblaster knocked on a window and asked the person inside to plug it in so we could listen to the hits. But even in that crowd, I felt different, superior. Did they know? Did they really know?

And now Prince has died and he's on every front page, and I want to buy a copy of each one to prove to somebody, somewhere: this is how famous he is, this is how special. It's stupid, pointless, untrue, but still I want desperately to say: he was mine before he was yours.