Lady Gaga's former assistant Jennifer O'Neil has signed a $1 million book deal for a tell-all book named "Fame Monster".

O'Neil worked with Gaga during the superstar's 2009 to 2011 Monster Ball tours and sued her in 2011, claiming that the "Poker face" singer owed her over a pay of 7,000 hours of overtime.

The former assistant of the star has not yet delivered her manuscript. However, legal documents from her court battle with the singer gives an insight into the 'monstrous' material that can be expected, reports contactmusic.com.

O'Neil was 'required' to sleep in the same bed as Gaga 'because she didn't sleep alone' and was also expected 'to be working and available 24/7' for a salary of just $75,000, testified O'Neil against Gaga.

"I had no privacy, no chance to talk to any family, no chance to talk to any friends, no chance to have sex if I wanted to have sex. There was no chance to do anything," she added.

Gaga fought the lawsuit, which the former assistant later agreed to settle out of court for undisclosed terms.