Despite having tumultuous relationships in the past, Harry Styles and girlfriend Nadine Leopold appear to be serious with each other. Friends of the 1D crooner reportedly cannot help but commend the 21-year-old's devotion to his current flame.

However, Harry Styles' girlfriend Nadine Leopold might not feel good about the news that one of the Brit crooner's exes is about to write a tell-all book.

Prior to being famous worldwide, Styles and the rest of his band mates including Niall Horan, Liam Payne, Louis Tomlinson, and Zayn Malik were contestants in the hit show, "The X Factor." Apart from his talent, the then 17-year-old Harry Styles made headlines for being in a relationship with then 32-year-old Caroline Flack.

According to reports by the Mirror, Flack has been asked to write a tell-all book in exchange of a hefty fee. Publishers are allegedly urging her to reveal details about her former relationship with Harry Styles.

The 1D singer's ex is allegedly asked to even include photos in the tell-all book. Apart from Harry Style, Carolina Flack also had romances with James Arthur and Sam Smith's manager, Jack Street.

Harry Styles' girlfriend Nadine Leopold is yet to comment about the issue.

The 1D singer and the Victoria's Secret model met last November but reports claimed that Harry Styles already invited his girlfriend to live with him.

Previously, it was reported that the Austrian beauty didn't feel delighted that Taylor Swift's still writing songs about the 1D member.

"Nadine really wants Taylor to get over him. She wants Harry to herself and doesn't think it's right for Taylor to draw this out anymore. She wants Taylor to go away," said one source to Life and Style magazine.

The insider claimed that Harry Styles and Nadine Leopold "feel like wherever they go, they are hearing Taylor's songs on the radio."

Some of Taylor Swift's songs believed to be written about Harry Styles include "I Knew You Were Trouble," "Out of the Woods," and the infamous "Style."