Perky Goth

Anime & Manga

 * The disturbing cheerful Undertaker in Black Butler.

Toys

 * In Monster High the young vampiress Draculaura fits this trope to a T. Her friend Frankie Stein really belongs here too.

Western Animation

 * Lydia, from the Animated Adaptation of Beetlejuice. (Not the near-suidicial emo kid from the movie, although she did lighten up at the end of the movie and new wardrobes are expensive.)
 * Craig of the Creek has Tabitha and Courtney, two teenage goth girls who are dubbed "The Witches of the Creek" by the elementary school aged main characters. The two (particularly Tabitha) are amused by the intimidating witch image the kids have of them and enjoy messing with them, but they're very playful and even end up helping the kids a few times.
 * Total Drama, Gwen fits this bill pretty well when she's in a good mood.