Simon Cowell made a point of ordering his boot camp hopefuls not to become romantically involved with each other.
So he is bound to lose his famous temper when he finds out that Cher Lloyd and Aiden Grimshaw are secretly in love.
X Factor sources say Cher, 17, has grown increasingly close to 18-year-old Aiden - who became a bookies' favourite after his performance on Saturday night - and the pair got together during boot camp.
The news is sure to infuriate Cowell after his strict dictum to housemates and comes after the supremo instructed his minders to keep a close eye on any of the performers under the age of 21.
Last night, the boot camp insider told the Daily Mirror: "Cher and Aiden are both really keen on each other and basically spend every free minute together.
"Cher had a crush on Aiden right from the start but it took a couple of weeks for the feeling to become mutual.
"They are desperate to keep their romance a secret because, given recent events, relationships between the contestants are really frowned upon in this series.
"Simon has laid down the law with the boot camp people and insisted there would be no girls in the boys' rooms after dark, no relationships, no drinking, no smoking, no e x c e s s i v e noise and no bad behaviour. He made it very clear no one is bigger than the show and everyone is expendable, so if they break the rules they are out."
Terrified their romance will lead to them being kicked off the hit ITV1 show, the singing sensations are trying to keep things under wraps.
The source added: "Obviously they have been trying to keep things lowkey when they are out in public.
"They aren't being overly affectionate with each other in front of the other cast and crew members, but they have been spotted on more than one occasion.
"But the minute they get some free time they seek each other out and spending lots of time gazing into each other's eyes and fooling around.
"It's fair to say that everyone in boot camp knows that they have fallen for each other. It's so obvious."
Blackpool boy Aiden is the second contestant on the show to have been romantically linked to Cher, from Malvern, Worcs.
She is also said to have grown close to 16-year-old Liam Payne - but the teen sensation insists the pair are just good friends.
