The Vamps star Brad Simpson was left startled when a fan asked for a toilet selfie mid-pee.
The boy band member was minding his own business when a fan appeared next to him at the urinal and asked for a picture with him, and he feared he could get a snap of his manhood.
Drummer Tristan Evans told the Daily Star: "It happened to him [Brad]!"
Frontman Brad recalled: "It was a kid, he asked if he could have a photo and I was like 'You can if you let me finish doing my business!'
"Your guard is down, luckily the kid didn't have his phone in his hand but all it takes is 'oh the camera has flipped the wrong way'."
The 'All Night' hitmakers are preparing to mark their 10th anniversary, and they have a few surprises up their sleeves for fans.
Guitarist James Brittain-McVey said: "We're planning loads of things around the ten years, we're coming up to ten years since quite a few things.
"Whether it's the first album, the first song, first tour, all that stuff, over the coming few years there might be a few things happening to commemorate certain moments.
"We're definitely strategising things at the moment."
Already confirmed, the group - completed by bassist Connor Ball - are re-imagining their hits for a special celebratory project.
Brad added: "We're so proud of all the things we've done, it's not one of those where we're trying to be dismissive of anything.
"We genuinely go back and breathe new life back into new songs."
It will include fan-favourites such as 'Can We Dance' and 'Wild Heart'.
The Vamps formed back in 2012.
As well as topping the charts, the lads' achievements include being the first band to headline London's The O2 arena five years in a row.