It sounds a lot dirtier than it is.
All it involves is dangling your fingers seductively in front of your mouth.
18-year-old Kylie Jenner is basically the pose’s mascot.
Click through the gallery below to see Kylie’s fingermouthing mastery.
Buzzfeed, which coined the term, says the pose is intended to look careless and candid.
But of course, we all know that isn’t the case – particularly when you note just how often this particular pose pops up.
Fingermouthing is said to help frame the face, bring focus to your lips and can show off newly manicured nails.
But while Kylie is the true early adopter, her sisters have also jumped on board.
Here we have Kendall fingermouthing.
A photo posted by Kendall Jenner (@kendalljenner) on Jul 2, 2016 at 8:21am PDT
Big sister Kim Kardashian.
A photo posted by Kim Kardashian West (@kimkardashian) on Mar 31, 2016 at 10:14am PDT