The 33-year-old opened up about his dad's battle with alcoholism, detailing his fall from grace with stories from his own childhood.
CBB star Calum recalled a time when he was 12-years-old. George returned home drunk, only to mistaken his son for a woman.
Previewing the book on the MailOnline, Calum said: "I am about to start trying to go back to sleep when Dad rolls over, puts his face in front of mine and kisses me: as in, he puts his tongue in my mouth. That kind of kiss.
"I freeze. What's going on? I'm old enough to know what a French kiss is. But why is my dad doing it to me?"
Calum revealed that, because of his drinking, George would regularly fly into a rage, taking it out on his son.
Another time, when he was hanging out with his dad's fiancée Alex, Calum said George came home only to suddenly turn on both of them.
He said: "I realise what he must be thinking. My drunk, old, alcohol-poisoned dad is convinced his 14-year-old son and his beautiful young fiancée are getting it on behind his back."
According to Calum, George got angry. He turned on Calum, shockingly raging: "You're not my son."
"He's never spoken to me like this before," Calum added. "My father, me hero, is telling me I'm not his son."
In November 2005 George died aged 59, from multiple organ failure. At the time of his death, Calum said: "Not only have I lost my dad… we've all lost a wonderful man."
Second Best: My Dad and Me is available to pre-order now for £11.89
From reality TV to fatherhood: Calum Best's life in pictures
From reality TV to fatherhood: Calum Bestu2019s life in pictures
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Calum Milan Best
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Born February 6 1981.
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He was born in Malibu and raised in LA. He moved to London when he was 21.
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Calum is the son of the footballer George Best and model Angie Best.
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His father George died in 2005 aged 59, after suffering from multiple organ failure.
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He rose to prominence when he appeared on the ITV reality show Celebrity Love Island in 2006.
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Calum is well-known for being a ladies’ man, having had relationships with many high profile women.
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He and model Jodie Marsh dated for four months in 2003.
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In 2005 he dated Girls Aloud star Sarah Harding. They were together for around two years. Last year he revealed they once spent three days in bed together.
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Things got steamy between Calum and David Beckham’s former PA Rebecca Loos while they were both on Celebrity Love Island.
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He met Bianca Gascoigne while on Love Island, and they are believed to have had a short relationship after the show.
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In 2006, Calum had a short relationship with model Lorna Hogan. She fell pregnant and gave birth to their daughter Amelia Lucie Hogan.
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Calum and Hollywood actress Lindsay Lohan briefly dated in 2007.
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In 2013 Calum admitted to cheating on model Georgia Salpa with presenter Donna Air.
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MTV’s Totally Calum Best debuted in 2008, which saw Calum attempt to remain celibate for 50 days and 50 nights.
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Calum filed for bankruptcy in 2013, saying at the time: “I can confirm I have made the decision to declare myself bankrupt as a result of being unable to make tax repayments.”
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Calum filmed scenes for the lead role in the movie Countryman in 2014. He also appeared in adverts for Rolls Royce in Dubai.
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In November that year, Calum underwent his third £6,000 hair transplant.
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He’s tipped to enter the Celebrity Big Brother house in January 2015.