Hands shot to mouths when he dropped to his knee in Venice. Though the gasps were of horror, not surprise. The only person who reacted differently was the gondolier who probably saw this every day and, quick as a flash, had fished a fistful of rose petals from his satchel and begun sprinkling them. It was a petal landing in her crisp packet that wrested her attention from her phone. I swear I saw her eyes roll when she realised what was happening.

As we floated in our own boats just yards from the horror, I sensed I wasn’t the only one with a sinking feeling in my guts. Since Rome, all forty of us had watched her treat him like a skivvy while she flirted with anything in a tight shirt. I was sure it was just me who’d seen her leaving the disabled loo with the tour guide one morning, but that didn’t mean the others hadn’t witnessed their own sights.

We couldn’t see his eyes, but his entire body was shaking as he croaked out a clearly rehearsed speech. She’d dropped her sunglasses over her eyes and seemed to be looking over his shoulder. Perhaps she was trying to decide if we’d turn nasty when she popped his heart like a balloon. A shrug suggested that, ultimately, she didn’t care.

He was reciting a poem. I could feel the heat under my ears and wondered if I should throw myself into the canal to save him. The water didn’t exactly look clean.

Finally, in broken words, as the world seemed to hold its breath to give the agonising moment maximum exposure, he asked. We watched her body stiffen and clamped our teeth together. I hoped she might at least have the decency to lean in and whisper her rejection, but I knew she wouldn’t. She took a deep breath, looked at the boy like he’d shat the bed, and opened her mouth.

‘Are you fucking stupid?’

We heard the contempt in every syllable. He didn’t move, frozen as he snapped from his nervous trance and realised just how centre stage his devastation was about to become.

What followed was not gentle. It was a demolition. She tore the boy to shreds. Every aspect of his personality, of his appearance, and of her complete lack of attraction to him. I suspected she’d be unkind, I hadn’t expected brutal. By the time it finished she was on her feet and his face was buried in his hands. Tears were flooding between his fingers.

I don’t think I’ll ever know if it was the gods or the gondolier which made it happen but, just as we clamoured for an escape, hands were sent to mouths once more, but this time eyes were wide with laughter.

It turns out, you see, that not all canals in Venice are so deep as you might think. In fact, if a particularly obnoxious woman in a short dress tumbles gracelessly overboard and splashes down onto all fours, there is, in some, just enough water to cover thighs and forearms, but not enough to stop a cackling crowd taking photos of her bared arse as it emerges like a pair of sodden bulbs from the fetid blue.