A character's face is pressed up against a foot.

Feral tagging

While this tag definitely applies to any appendage attached to the end of a hindleg, it is unresolved whether this tag should apply, or always apply for appendages attached to a foreleg. In many cases, especially with semi-anthro characters, the forelegs are often treated as analogous to arms, and as such the hand_on_face tag would be more relevant.