What makes  someone a monster? What is "good" and what is "evil", and how can connotations of those words be subverted?

For my narrative, I wanted to explore one where I can showcase a role reversal of our perceptions of what is a monster, showing a human monster hunter that is more evil than the actual monster they are hunting. This came in the form of an album package with a cover, an internal panel, and a back cover.