>>45266986It's a Pokemon based around a creature of deception and foul play, which is entirely what Dark type is all about.
That creature is itself of Japanese mythos and Mawile could be considered a trickster, which is why it was given Fairy type.
Mawile's Steel typing feels like an "ackchyually, its teeth are steel horns..." reach they added to its dex entry last minute to add more Steel types to Hoenn's regional dex.