Synopsis

Daniel Slade is what you would call a successful serial killer. He lived until 90 having murdered hundreds and never being caught for it.
When he died peacefully in his sleep next to his wife, Daniel expected to wake up burning in hell, but instead, he woke up reincarnated as a rich South Korean chaebol.
This wasn't just any ordinary reincarnation, the world he had been reborn into was the world from a novel that one of his victims had written, and the Chaebol he had reincarnated as was a third-rate Villain used to encourage the hero of this story.

Finding this new world, Daniel smiles to himself and thinks, "Let's show them a true Villain"