Harry Styles sent fans wild as he took part in "one of the most disgusting traditions ever" while on stage in Perth.
The former One Direction man joked how he will be discussing the moment with his therapist "at length" as he said he "felt like a new person".
Harry, 29, stunned onlookers Down Under when he agreed to do a "shoey" and drink from his own shoe.
As fans recorded the surprising occasion, Harry was pressured into taking part in the Aussie "tradition" after one of his entourage had previously done so.
Bowing to the chants, he removes his trainer to the delight of the audience. He then takes his Adidas footwear to the side to fill it up before returning front and centre to down the drink as the crowd screams.
One Direction now - comeback plans, car crash interview and lots of daytime TVBefore he completes the feat, he tells his fans: "This is one of the most disgusting traditions ever."
After pouring the liquid into his mouth - making sure he gets every drop - the Watermelon Sugar singer places his shoe back on before wiping his face and looking bemused at what he's just done.
"I feel like a different person," he gasped after removing the microphone from its stand.
Giving a giggle, he continues: "I feel ashamed of myself. It feels so personal. Such an intimate moment to be shared with so many people. It's fine when Scott does it."
He then jokes: "I'll be discussing this with my therapist at length. At length."
A fan can then be heard shouting among the screams: "Peer pressure," before the singer ends on a serious note by thanking those who have helped him on the tour so far.
The scenes come just a week after Harry shared a smooch with Lewis Capaldi at the BRIT Awards.
Despite walking away with four gongs, it was the smacker that grabbed the attention of his followers and bandmate Niall Horan.
Irishman Niall was later found to have text pal Lewis to call him a cheat after seeing the clips. The Scottish singer revealed the blunt interaction at his gig the next day before joking he was going to plant a peck on Louis Tomlinson next.
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