Jonas Venture Sr.

Jonas Venture is the father of Rusty and Jonas Venture Jr. While at first he appears to be heroic, it eventually turns out that he is a horribly abusive father who has endangered his own son time and time again.

In addition, he also blackmailed his partner Blue Morpho into doing what he wants using a sex tape.

Trivia
He can be considered to be the most hated character on the show, being more evil than series villain The Monarch.