Though there's been much speculation about Kylie Jenner's plump pout, in an upcoming episode of "Keeping Up With the Kardashians," the 17-year-old reality star finally stops playing coy and reveals the truth.

"I have temporary lip fillers, it's just an insecurity of mine and it's what I wanted to do," she confirms in a new clip. "I'm just not ready to talk to reporters about my lips yet because everyone always picks us apart."

"I want to admit to the lips but people are so quick to judge me on everything, so I might have tiptoed around the truth, but I never lie," she adds.

VIDEO: Kylie Jenner Fights Back at Criticism Surrounding Her Big Lips

Her big sister Khloe Kardashian also weighs in on the situation in the new episode, advising Kylie to just come clean.

"Kylie decided to plump her lips and I don't think there's anything wrong with that," she says. "I think if you've done something though, it is right to cop up to it."

Khloe herself obviously has no trouble admitting to procedures -- in the same episode, she lets cameras in on a doctor lasering off cellulite on her famous booty.

"It stings like a mother!" she cries.

Kylie's lips have become a full-blown social media phenomenon, and even spurned the somewhat disturbing #KylieJennerChallenge, in which people attempt to get Kylie's full-lip look through some pretty questionable means.

"I'm not here to try & encourage people/young girls to look like me or to think this is the way they should look," Kylie wrote in response last month. "I want to encourage people/young girls like me to be YOURSELF & not be afraid to experiment w your look."

NEWS: Scott Disick Says It Takes Kylie Jenner 40 Minutes a Day to Get Her Famous Lips

Last October, Kim Kardashian weighed in on Kylie's lips, claiming it was all lip-liner.

"I go into her room and I'm like, 'What liner do you wear?' because she only wears lip-liner and then she fills it in," Kim said, adding, "She doesn't wear a lipstick or a gloss."

SHE SAID/HE SAID: Sick of Deflategate? Or is fun just starting?