King Oberon is the former ruler of Fairy World along with his wife Queen Titania at least according the video game The Fairly OddParents: Shadow Showdown. Wanda states they're ony figureheads now.
Titania speaks in a very stereotypical royal English accent. She's fond of telling other people "Silence!". As with King Oberon, her canoncity is, at best, questionable.
Oberon seems to be even more of a figure head than the queen as he seems to only repeat what the Queen says.