Los Angeles, If the grapevine is to be believed, singer Beyonce Knowles is cheating on her husband and singer Jay-Z and she is reportedly having an affair with her bodyguard Julius De Boer.

Jay-Z, who got married to Knowles in 2008, is said to be suspicious about her close relationship with Boer, reports showbizspy.com.“Jay definitely thinks that there was and may still be something romantic going on between Bey and Julius.

He wanted to fire Julius last February, but Beyonce said- ‘Julius isn’t going anywhere’,” said a source.In 2009, Knowles, 32, and Boer were spotted leaving a hotel. Boer’s lips were stained with the singer’s signature red lipstick.Despite being subject to numerous cheating rumours himself, Jay-Z is jealous of his wife’s friendship with her bodyguard.

“They’ve spent a lot of time together behind closed doors. He’s even stayed in her hotel room,” added a source.Beyoncé’s bodyguard, Julius De Boer, became instantly famous when — on surveillance video captured in a hotel elevator after the Met Gala — he saved her husband, Jay Z, from a brutal attack at the hands of her sister, Solange Knowles.

On the video, Julius comes across as professional, loyal and level headed. But while all that may be true, Star has learned that there’s a lot more to the bodyguard — and his relationship with Beyonce — than meets the eye.

“Jay definitely thinks that there was and may still be something romantic going on between Bey and Julius,” an insider tells Star of the hip-hop mogul, whose own rumored cheating was the reported cause of Solange’s attack. “He wanted to fire Julius last February, but Beyonce said, ‘Julius isn’t going anywhere.’”

The “XO” singer and her bodyguard have raised eyebrows for years for their unusually close relationship. In 2009, they were spotted leaving a hotel, his lips stained with the signature’s signature red lipstick. Despite being subject to numerous cheating rumors himself, Jay is, nonetheless, “very jealous” of his wife’s friendship with Julius — and friends believe he may have a reason to be.

“They’ve spent a lot of time together behind closed doors,” the source explains. “He’s even stayed in her hotel room.”

Julius isn’t the only man to come between the power couple either.