During his time in the house, viewers watched Calum flirting with housemate Cami Li after striking up a close friendship. But despite looking pretty cosy at times, both admitted to each other - cryptically - that they were in fact taken.
And now he has left the house, Calum has confessed he kept his girlfriend a secret because he didn't want to "jeopardise" his spot on CBB!
Reports suggest Calum has been dating model and former Made In Chelsea star Ianthe Rose Cochrane-Stack since last year.
But making no mention of her in his VT for Celebrity Big Brother, Calum revealed to The Sun he purposefully said he was single to win his place in the CBB house.
"Going on the show, I was conscious like a few others that I wanted to be 'single'," he said. "Celebrity Big Brother wouldn't touch me for years and I've worked hard for this chance - so I wasn't going to jeopardise it by saying I was taken."
On the show, Calum was seen brushing off advances from US model Cami, and pleased he didn't give the viewers the house romance that they wanted, the 34-year-old said he did himself "proud" by not giving in to his housemate's charms.
Instead, the model claimed he was too busy thinking about his girlfriend on the outside world - and in more ways than one...
He said: "I thought about all sorts of stuff in the house and it was definitely explicit... I've changed, but I'm always going to have a naughty side."
During Friday night's final, Calum was voted in third place by the public. Katie Hopkins came in second and it was Katie Price who was crowned as the CBB winner for this series.
Following her win, Katie P faced criticism from Katie H who claimed she was an undeserving winner.
Speaking on CBBBOTS, Katie H told Rylan it was a "complete con" that Pricey had won.
"All she did was complain about her t*ts, complain about her life, complain about her sex life and talk about poo. Frankly that's not good enough for me," she said.
Not impressed with the way his friend handled coming second, Calum criticised Katie H for "not losing in the nicest way possible".
Showing his support for Katie P, he said: "I'm happy for Katie Price winning it."
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