Who's the biggest diva of them all? 

What better person to find out all the gossip from those who have worked with them exceptionally close? 

These former personal assistants have spilled on beans on their most shocking stories about their A-list bosses. 

Here are some of the celebrities who are a nightmare to work with.

Lady Gaga

Lady Gaga
(Photo : Photo by Jamie McCarthy/Getty Images)

"A Star Is Born" actress and singer Lady Gaga reportedly doesn't want to be left alone, so she required her assistant to be with her 24/7 that she had no time to "talk to family, talk to friends and no chance to have sex."

One weird thing was even required to sleep in the same bed as the pop star and showered with her. 

The singer was sued for unpaid overtime for nearly $400,000. 

Kylie Jenner

Kylie Jenner
(Photo : Photo by Matt Winkelmeyer/Getty Images for The Recording Academy)

Since her childhood, a rich and pampered girl, it's not surprising that Kylie Jenner expects people to do things for her.  

Former staff of the highest-paid celebrity has revealed that this goes to somewhat ridiculous extents. 

According to them, the "Keeping Up With the Kardashians" star barely does anything herself. Kylie even uses her housekeeper's arm for arm swatches when she has new products to launch for Kylie Cosmetics. 

Christian Bale

Christian Bale
(Photo : Photo by Jason Merritt/Getty Images)

Too bad for former assistant Harrison Cheung, who used to work for "Batman" star Christian Bale. 

He claimed that the actor would ask his assistant to do just about anything, from sniffing Christian's armpit for body odor before walking the red carpet. 

Other times, Harrison is forced to go on "sock runs" if the actor was all out of clean ones. 

Ariana Grande

Ariana Grande
(Photo : Photo by Jason Merritt/Getty Images)

A tipster once told NY Daily News that Ariana Grande's latest rule included carrying her around like a baby. 

When she doesn't feel like walking, the "Thank U, Next" star would ask her assistant to pick her up. 

Angelina Jolie

Angelina Jolie
(Photo : Photo by Anthony Harvey/Getty Images)

Many of her former housekeepers revealed that they have seen Angelina Jolie throwing a few tantrums, whether she is with her kids or having disagreements with her then-husband, Brad Pitt. 

Khloe Kardashian

Khloe Kardashian
(Photo : Photo by Jerod Harris/Getty Images for A+E Networks)

Khloe Kardashian doesn't like lifting a finger at her house, according to Radar Online, as she barks orders at her assistant and housekeepers for whatever she may like. 

Justin Bieber 

Justin Bieber
(Photo : Photo by Jerod Harris/Getty Images for A+E Networks)

Once, Justin Bieber was caught carrying an illegal substance to the airport. 

Unfortunately, his assistant at that time, Terrance Reche Smalls, suffered the effects and took the fall for the singer. 

He pleaded guilty to two charges of marijuana and was handed a 12-month good behavior bond. 

Terrance was also forced to pay a fine of $1,000, but surely Bieber had to pay that and additional fees for tarnishing his assistant's name in the law. 

Mariah Carey

Mariah Carey
(Photo : Photo by Neilson Barnard/Getty Images)

In a filed lawsuit in 2004, Mariah Carey's personal assistant claimed that she made him work 16-hour days with no overtime pay or meal breaks. 

The diva doesn't even wash her own hair, as per the former PA, as she hires a professional do it or her own assistant. 

Madonna

Madonna
(Photo : Photo by Ilya S. Savenok/Getty Images for A+E)

Because she's such a germophobe, Madonna's staff walked out after one work of working at her home because she made all her team work 24/7 and made them all go on a macrobiotic diet.

Ellen DeGeneres 

Ellen DeGeneres
(Photo : Photo by Christopher Polk/Getty Images for The People's Choice Awards)

A former staff of the "Be Kind" host revealed she was the subject of racist micro-aggressions and abuse. 

News of Ellen DeGeneres' mean-spiritedness is consistent, as many ex-employees come forward with stories about her.

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