Complex sentence: The Monarch is one of the main characters and primary antagonist on the Adult Swim show "The Venture Bros.", and is a parody of a supervillain who has modeled himself after the Monarch butterfly.
Split into simpler sentences: The Monarch is one of the main characters and primary antagonist on the Adult Swim show "The Venture Bros.". He is a parody of a supervillain, who has modeled himself after the Monarch butterfly.