Supervillain should be written as one word, the same way superhero is.
When used as names, Mom and Dad are capitalized. If you don’t want to capitalize them here, say their mom and dad instead.
Evil and supervillain are sort of redundant, don’t you think?
Also, why is the villain super, but the hero isn’t? That’s not fair. I bet the hero complains bitterly to their parents about it: “You always liked Marcie better! You let her be a super villain, but I’m only allowed to be a regular hero. Look, you’ve even given her a brand-new Supervillain Lair play set, and all I get are a bunch of Eighties-style sweaters… again.”
(Yes, I do have fun writing these things. Why do you ask?)
The supervillain and the hero are siblings. They still have dinner at Mom and Dad’s house for the holidays.