WATCH: Ellen Degeneres Grills Kourtney Kardashian About Justin Bieber

We’ve never seen Kourtney Kardashian squirm like this before.

Ellen Degeneres asked the eldest Kardashian about her rumored hookup buddy Justin Bieber, and her flustered expression said it all: she’s smitten.

The 36-year-old mother of three insisted through a wide smile that she and the Biebs were nothing more than “just friends,” but Degeneres remained skeptical, pressing further by asking her “Why are you smiling that way? You’re smiling as if that maybe it’s beyond friends.”

Way to blow their cover, Ellen. Kourtney proceeded to engage in typical avoiding-the-question behavior by taking a sip of water.

The show host also asked Kourtney about her younger sis Kendall Jenner and beau Harry Styles, with whom she and wife Portia de Rossi spent some time with at St. Barts. Ellen proposed, “They’re a cute couple.”

“I don’t know! You know more than I do,” Kourtney said coyly, revealing that she’s never met the One Direction singer.

Later, they Facetimed with Khloé Kardashian, who revealed that she was with Lamar Odom at her home.

“Lamar is doing great, by the way, he was over over the weekend,” Kourtney added.

Khloé explained, “He’s really good. I just told him I had to go Facetime you guys…His long-term memory is great, his short-term memory isn’t so good…”

“He’s hung out with Kourt’s and Kim’s kids and he loves family time, so he’s been doing really good. I think it makes him feel good to be around everyone too and to just be in a happy environment over, obviously, where he was.”

“We’ve explained to him the situation, and like we were told he had four hours to live, so it’s like a miracle, really,” Kourtney added.

Watch the interview in the video above, in which Kourtney also discusses her new app.