tail mouth
This applies when a working mouth resides at the end of a character's tail. The mouth works either independently of or in conjunction with a character's first mouth. In some cases, the tail might seem to have a mind of its own. When this and the regular mouth on somebody's face are both clearly seen, also use multi_mouth.
If the tail appears to be sentient and/or has a head, living_tail and/or tail_head could also be applicable.
Related tags
The following tags are aliased to this tag: mouth_tail, tailmouth, tail_maw, tailmaw (learn more).
This tag implicates unusual_tail (learn more).