The model revealed that their romance began at Rachael's home after they shared a kiss:
"We kissed one night at her house and then it led to that. A drunken kiss. Just us at her place," she said.
In a cryptic Instagram post following her elimination, Vakoo shared:
"I may not have found love with the Bach but I found love with some extraordinary women."
As it turns out, the women vying for Matt’s heart were intimate on more than one occasion during their stint in the mansion.
"We all showed each other our vaginas," Vakoo told Kyle and Jackie O earlier this month.
"It’s fascinating. You’re looking and you’re like, ‘wow, so yours is like that? Mine’s a bit different’."
Around that time, intimate images emerged of Rachael and Vakoo sharing a passionate kiss while out on a dinner date together.
At one point, Vakoo was seen placing her hand gently on Rachael’s face as they locked lips for several seconds before sharing a toast.
WATCH: Ex-Bachelor star Vakoo talks about her relationship with Rachael and the moment she tried to kiss her in the house
A source claimed, "Rachael and Vakoo formed a really strong friendship in the mansion and their feelings for each other quickly developed into something more. They ended up hooking up in the mansion one night after one of the first cocktail parties. It was never filmed and producers never found out about it.
"They started spending lots of time together after that. The girls would always see them together, going for walks alone, and started to question if they were more than friends but they never confirmed it."
The pair’s secret rendezvous followed months of social media flirting and reports suggesting series villain Rachael had hooked up with a producer on the show behind the scenes.
"Thankful we went on this crazy journey or I wouldn’t have met my soulmate," Rachael captioned a snap of her and Vakoo on Instagram, to which Vakoo responded: "I love you so much!"