Grace Davies, 19 and Matt Linnen, 28, ‘hook up’ in The X Factor house

X FACTOR stars Grace Davies, 19, and Matt Linnen, 28, have reportedly "hooked up" in the contestants' mansion.

The Daily Star reports the singers have grown close and "have already slept together".

A source said: "Matt and Grace aren’t dating – it was basically just for fun.

"They now act as if nothing has happened.

"This is the sexiest series yet.

"There are a lot of attractive people in the house so some contestants are bound to be hooking up.

"But contestants are worried that people talking about flings will affect the votes - they’re petrified their fans will turn their back on them.

"Nobody has done anything wrong, at the end of the day Grace and Matt are both single."

A spokesperson for The X Factor said they did not wish to comment at this time. 

Grace and Matt's rumoured fling comes after the Cutkelvin brothers warned their sister Sheeran off hooking up with anyone in the house.

Jay and Kay have warned their sister to "keep her eyes to herself" as she's surrounded by lots of good looking guys on the show.

Shereen, 20, is the boys' younger sister and together they formed music group The Cutkelvins.

When asked about living with lots of boys, she told The Sun Online: "I love it."

But Jay quickly cut it to joke: "In all seriousness, keep your eyes to yourself - you're not allowed to touch anyone until you're 41."

Shereen then quipped: "He's put it up a year, it used to be 40. He said I'm not allowed to have a boyfriend until I'm 40."

When asked if there was any chance of romance blossoming in The X Factor house, Kay said: "It wouldn't happen, she's banned and her other brothers back home have banned her as well".

But Shereen was quick to point out the same rules didn't apply to everyone in their family.

She said: "I've a younger sister as well but she's got a boyfriend."

Jay added: "It's different when you've actually got to stay with your sister".

• The X Factor continues tonight at 7.05pm on ITV

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