Mawile

Mawile (クチート) is a fictional Steel-type Pokémon found only in the Ruby version. It is a third-generation Hoenn Region Pokémon that stays mostly in caves. The horns on its head are actually super-developed jaws which it will attempt to use on anyone who comes too close. Its docile-looking face serves to lull its foe into letting down its guard. When the foe least expects it, Mawile chomps it with its gaping jaws.

In the Anime, Ash's Corphish falls for a Mawile who apparently doesn't appreciate his affection. she later becomes smitten with Lombre when he saves her from one of Team Rockets' schemes, but goes off with a Psyduck when he evolves into a Ludicolo.