Veronica (South Park)

Veronica was a villain that appeared in South Park - she was the chief antagonist of the episode "The Succubus".

Veronica was, as the title of the episode suggests, a succubus and planned on marrying Chef in order to destroy his soul - her demonic influence altered Chef's behavior from a singing free-spirit to a rather dull individual.

Veronica also gained control over him via singing the love theme "The Morning After" - the boys found out that by playing her song backwards they could free Chef and did so.

Veronica lost control of her powers as a result and transformed into her true demonic visage and was sucked back to Hell, freeing Chef - who promptly apologized to the boys for his behavior.