The Monarch is Dr. Venture's arch nemesis on The Venture Bros. The Monarch's revilary with Dr. Venture is definitely more one-sided and pretty much the funniest thing ever. The Monarch modeled himself after the Monarch butterfly after they "raised him" when his parents died. The Monarch is wealth from his dead parents.
The Monarch married his girlfriend, Dr. Girlfriend, who is now known as Dr. Mrs. The Monarch. Yeah, nothing short of amazing.