A heavily pregnant girlfriend, who fatally shot the father of her child in a botched YouTube stunt, cried and pleaded with him to stop moments before the tragedy, new court documents have revealed.

Monalisa Perez, 21, told Pedro Ruiz III “I can’t do this babe, I am so scared” as he urged her to fire a high-calibre pistol into a book he was holding in front of his chest.

A transcript of the video, released Friday, detailed how Ruiz, 22, reassured his girlfriend that the 1.5-inch hardcover encyclopedia would stop the bullet, as they filmed the stunt outside their Minnesota home in June last year.

However the shot from the .50-caliber Desert Eagle Perez fired from point blank range penetrated through the book and fatally wounded the aspiring YouTuber.

The stunt took place in front of 30 witnesses including Perez and Ruiz’s three-year-old daughter.