I looked the author of that, expecting Montefiore since it's right his methods, and while it's surprisingly not Montefiore (i guess not enough pedophilia accussations for him), but dude named Li Zhisui, even his wiki is pretty much telling:

After emigrating to the United States, he wrote a biography of Mao entitled The Private Life of Chairman Mao, in which he described Mao as selfish, cruel, having a craving for young women, and poor personal hygiene.

After emigrating to the United States