Harry Styles has reportedly been two-timing Kendall Jenner.
The One Direction hunk is said to have recently enjoyed a night of passion with fashion stylist Pandora Lennard, 27, even though he is currently dating the American model.
A source who knows Harry and Pandora said: "Everyone knew they were attracted to each other and they have been pals for a while.
"But we didn't think anything would happen as Harry and Kendall are officially an item. This is gobsmacking."
The tryst is reported to have happened at his £3.5 million property near Hampstead Heath, North London, just a few days after he was spotted kissing and cuddling with Kendall, 20, while on vacation in the Caribbean.
Pandora is the founder of the Anti-Agency modelling company and has worked with a string of famous faces, including Little Mix, Fifth Harmony and Jessie J.
Asked about her reported fling with Harry, Pandora told The Sun on Sunday: "I have absolutely no comment to make."
Despite their burgeoning romance, doubts have been raised about Harry and Kendall's relationship, because the singer is based in the UK, while the American beauty lives in Los Angeles.
However, a source previously suggested they would work hard to overcome the potential problem.
The insider said: "They promised each other that they wouldn't let the long distance ruin what they had.
"So they have scheduled Skype sessions that typically last two hours and they text throughout the day when they can."