Bowser (Japanese: クッパ, Hepburn: Kuppa, "Koopa"), also known as King Bowser or King Koopa, is a fictional character and the main antagonist of Nintendo's Mario franchise. In Japan, he is titled Daimaō (大魔王, Great Demon King"). He is the arch-nemesis of the plumber Mario and the leader of the turtle-like Koopa race. Depicted as a fire-breathing monster with a tyrannical personality, Bowser's ultimate goals are to kidnap Princess Peach and conquer the Mushroom Kingdom. Bowser debuted as Mario's opponent in the 1985 video game Super Mario Bros.
https://en.wikipedia.org/wiki/Bowser