Probably The Homelander, from the mature graphic novel series, The Boys. In his own universe, he's supposedly the big saviour of the day, avenger of the innocent, the hand, head and heart of justice and all that. But when he's not fighting crime he's a sadistic, murderous, sexist bullyboy. And it's up to The Boys to expose those traits and let the public know that the word "hero" has been like this for years.
But other than heroes of The Boys universe, I can't say, sorry.