Very similar to the Gorilla Mask, the Yeti Mask involves removing aged grey and/or white pubic hairs and applying them firmly on a freshly facialled face so they stick to the face resembling a White Gorilla or Yeti.
Grandpa Joe: I was just having sex with Grandma and I Yeti Masked her.
Jonny: What's a Yeti Mask?
Grandpa Joe: It's when you rip out your old man pubes after giving her a facial and throw it on her face.
Jonny: I want to be Yeti Masked!!!