"I married a divorcee!" the actress, 34, told the WTF host.
When asked who her husband had been married to in the past, Kunis answered: "Demi Moore."
The mother of Kutcher's two kids insisted her husband shared a "normal" marriage with Moore, 55, before their 2011 split.
"They had a normal, real relationship," she defended of the May-December union, before referring to Moore's children with another ex-husband, Bruce Willis. "They had three kids they were raising. He loved those kids."
As RadarOnline.com readers know, Kutcher, 40, was spotted constantly throughout his marriage to Moore with her girls: Rumer, Scout and Tallulah.
She insisted Kutcher still shares a relationship with Moore's kids, who are all now in their 20's.
Kunis also admitted she started dating former That 70's Show costar Kutcher very soon after his divorce from Moore.
When Kutcher begged her to move in with him after three months of just "hooking up," "he had only been single at that point for about a year," she confessed.
Though she said she was hesitant, he insisted on staying with her, saying, "I'm not going to lose you."
As RadarOnline.com previously reported, Kunis had a fractured relationship with Moore in the past.
- Mila Kunis and Ashton Kutcher Blaming Each Other For Backlash Over Support of Convicted Rapist Danny Masterson: Report
- Ashton Kutcher 'Desperate' to Repair Reputation After Letter of Support for Former Costar Danny Masterson: Report
- Ashton Kutcher and Mila Kunis Fear Reputations Are Irreparably Damaged Over Danny Masterson Support
"But Mila just snapped and told Demi that she has had enough. She wants her to just leave them alone," said the source. "Demi didn't have any boys anyways, so Mila seems to feel like her advice is just quite comical."
Kunis and Kutcher have been married since 2015, two years after his split from Moore was finalized.
We pay for juicy info! Do you have a story for RadarOnline.com? Email us at firstname.lastname@example.org, or call us at (866) ON-RADAR (667-2327) any time, day or night.
Get the exclusive celebrity scoop on all the stars you love before any of your friends by subscribing to our new podcast Straight Shuter below!