Board Thread:False Info and Speculative Discussion/@comment-25119882-20140708145312/@comment-1600299-20140710070758

The closest thing in "real life" mythology is something called the Astomi, a Greek and Roman mythological race of mouthless people who did not eat or drink anything, they survived by smelling things

Doesn't mean the mouthless man in TW is this exact thing, but it's the closet comparison in own likelihood with it's own mythology or backstory