Reason Prince William got back together with Kate Middleton following split is surprisingly x-rated

If you think royal love is plain sailing, then you might want to think again.

Prince William and Kate Middleton have certainly had one of the greatest love stories of the century.

The two met while both were studying at the presigious St Andrews - though it took a while for them to get to know each other as the Princess of Wales recalled during their engagement that when they met, she went 'bright red' and William 'scuttled off'.

However, they managed to become 'close friends' and even lived together with their friendship circle - with the relationship soon turning romantic after Prince William reportedly saw her in the famous sheer dress during a charity fashion show.

However, the pair ended up briefly splitting after dating for five years, with Prince William saying they needed 'just a bit of space'.

Prince William and Kate Middleton pictured together in 2007 (Indigo/Getty Images)

According to Rob Jobson in his new book Catherine, The Princess of Wales: A Biography of the Future Queen, William brutally dumped Kate in a 30 minute conversation.

"He told her they both needed 'a bit of space' to 'find our own way', and he was unable to promise her marriage," Jobson said.

"In an emotionally charged 30-minute conversation, they both acknowledged they were on 'different pages'."

"I’m free!" he reportedly shouted in a book excerpt from The Daily Mail after ending the call.

But according to Jobson, it was Kate's resilience throughout the obviously heartbreaking situation that seemingly made William realise he'd f***ed up big time.

Jobson claims that the Princess spent her single era out and about with her sister, Pippa Middleton, at nightclubs and on holiday in Ibiza with some friends.

In his book, he wrote: "Seeing photographs of his ex‑girlfriend having fun and looking sensational was a bitter pill.

They have now been happily married for 11 years. (Max Mumby/Indigo/Getty Images)

"He soon began having serious second thoughts, though he realized that after the way he'd treated Catherine, it wasn't going to be easy to woo her back."

And their eventual meet up was supposedly more risqué than you'd imagine for a future King and Queen.

The pair bumped into each other at a Halloween party arranged by a mutual friend- with the theme being 'Freakin Naughty'.

According to Jobson, Kate allegedly 'arrived dressed as a nurse' and 'William had made a beeline for her'.

"The chemistry between William and Catherine did the rest. They then spent the first part of the evening deep in conversation before hitting the dance floor, where they ended up kissing,” Jobson claimed.

According to the expert, they then left the party together.

The Prince and Princess of Wales ended up getting married in 2011 and soon welcomed their children, Prince George, Princess Charlotte and Prince Louis afterwards in 2013, 2015, and 2018.

Tyla has contacted Kensington Palace for further comment on the matter.