In the tell-all, Moore says the two started dating while they were costars on the 1984 film "No Small Affair" and he fell for her hard. While they both agree on that part, Cryer fact checked her on another claim.
"Jon fell for me in real life, too, and lost his virginity to me while we were making that movie," she wrote. "It pains me to think of how callous I was with his feelings -- that I stole what could have been such an important and beautiful moment from him," she continued, saying she was not in a good place for a relationship at the time.
According to Jon, however, she wasn't his first.
"Well, the good thing about this is she doesn't have to feel bad about it anymore, because while I'm sure she was totally justified making that assumption based on my my skill level (and the stunned look on my face at the time), I had actually lost my virginity in high school," he tweeted out on Tuesday afternoon.
"But she's right the other part, I was over the moon for her during a very troubled time in her life," he added in a follow-up tweet. "I have nothing but affection for her and not a regret in the world."
In the book, Moore also talks about her troubled relationships with first husband Freddy Moore, fellow Brat Pack-er Emilio Estevez, Bruce Willis and Ashton Kutcher. See more of the most shocking, surprising and brutally honest bits from the book at the link below.