They've been in the industry for two years now, so you'd think One Direction would be used to their fans' antics - but the group was left stunned on a recent trip to Sweden when their female followers flashed their breasts at them.
The pop hunks have toured the world to promote their music since they shot to fame on The X Factor in 2010 - and the lads' trip to Sweden left a lasting impression on them.
Louis Tomlinson reveals that one group of overzealous fans ran after their car, lifted their tops and pressed their bare boobs against the windows.
Speaking to chat show host Alan Carr, he says, "The Swedish fans were pressing their breasts up against the car window."
Louis gave a demonstration of the stunt, but his bandmate Niall Horan admits he was left a little red-faced over the incident.
He adds, "It was quite embarrassing."
The group were special guests on the presenter's Chatty Man show, which is set to air on Friday night, and they also opened up about their other experiences of being pop stars.
Niall said, "After you have been on stage it sounds like you've been in a tunnel for 10 minutes because of all the screaming."
Notorious ladies man Harry Styles used his appearance on the sofa to dismiss reports linking him to singer Natalie Imbruglia after they met at James Corden's wedding earlier this month.