What are some boys names with negative meanings?

Dracul: A Romanian name meaning "devil" or "dragon."

Teivel: A Yiddish name for the devil.

Ubel: A German boy's name meaning "evil one."

Tristram: "Sad"

Mel: "From the bad or poor settlement". From the name Melville, Melvin, etc.

Dougal/Doyle: "A dark stranger."