The 38-year-old Good American founder called it quits with Thompson following another cheating scandal where he fathered a child with fitness influencer Maralee Nichols. The two share their four-year-old daughter True and newborn son born via surrogate whose name is yet to be revealed.
"Is there anything else you’d like me to ask you? Anything you'd like me to clear up?" Kourtney asked before addressing the elephant in the room. "Any rumors…any…oh! Are you sleeping with Tristan?"
"No, I am not. I'm really not," Khloe adamantly replied, doubling down on her answer as the poosh mogul looked to the polygraph examiner who confirmed her younger sister was telling the truth.
The mom of two then quipped, "I would die if it said I was!"
When it came to Kourtney's turn, the 43-year-old Lemme Sleep creator got candid about a variety of questions ranging from her involvement in the illuminati to keeping pieces of her children's hair in a safe.
The eldest Kardashian sister also opened up about the details of her sex life with her husband Travis Barker. If you've ever wondered if the couple have ever been caught "doing the deed" in public the answer is yes.
Khloe then asked if she regretted the experience, Kourtney answered with a firm, "no."
Kourtney and Travis said "I do" for the first time in a Las Vegas chapel after the Grammy Awards back in April and nobody in her family was present. Taking the test, Kourt confirmed she had no regrets about not inviting them.
Shortly after, the couple made things legal when they tied the knot at a Santa Barbara courthouse before having an official ceremony at L'Olivetta, a villa owned by Dolce & Gabbana in Portofino, Italy in May with their closest friends and family.
When Khloe was strapped to the polygraph machine, she admitted that while she enjoyed her time celebrating Kourtney at her wedding, she was less than thrilled about her sister's chosen wedding dress.
"It was fine," she admitted. "I mean, it was beautiful, for sure. I just would have loved to see you in that at the after-party and then something [else] prior."
Check out the full video above to see what Khloe thinks about her sister's style transformation thanks to Travis ... whether True will ever be able to sleep over at their home ... and which business mogul Kourt simply couldn't identify.