Derived from the term "sit on my face," which is a style of cunnilingus where the giver lies flat on the back and the receiver sits upright on the giver's face.
See the Monty Python song, "Sit On My Face" for more insight into this form of cunnilingus.
Can be used as a noun or as a phrase.
"Hey, baby. Cinnamon face!"
"My ex-boyfriend was a cinnamon face"