Interesting fact:

Mawile is a very strange-looking Pokémon; no surprise, it’s based on something even more peculiar. Futakuchi-onna are women afflicted with a curse or supernatural disease that sees a second mouth develop on the back of their heads. The second mouth eventually develops teeth and a tongue, along with a voracious appetite. This hunger is satiated by the mouth eventually taking control of the woman’s hair, using it to grab food and gorge itself. It’s said to form due to the woman in question eating too little, so the mouth does all the eating for her. Horrifying.