Goth Barbie was launched by Mattel, the maker of Barbie, in 2010 and the company never imagined it would become the second best-selling doll in the world.

The Goth Barbie has become a hot seller over the past few years and its popularity has continued to grow. The dolls of Monster High are now the second best-selling doll in the world, second to none other than the original Barbie, and it's continuing to grow as a franchise.

The message behind the Goth Barbie's of Monster High is to encourage girls to have confidence to be themselves and embrace their differences from what is conventionally considered beautiful or popular.  

Goth Barbie is inspired by monster movies and sci-fi horror legends such as "Medusa", "Dracula", "Frankenstein's Monster", and the "Creature from the Black Lagoon". Since these dolls are targeted at girls between the ages of 6 to 12, they are not as creepy looking as one may imagine a Goth Barbie would be.

"The message about the brand is really to celebrate your own freaky flaws, especially as bullying has become such a hot topic," says Cathy Cline, head of marketing for Mattel's girls' brands, according to NPR.  Overall, sales at Mattel have surged 56 percent this year, in large part due to the success of the Monster High franchise.

"And it's also one of the fastest growing brands within the entire toy industry," Cline adds.

Mattel's vice president of design, Kiyomi Haverly, has also commented on the popular collection and she's very surprised by its rapidly growing success.

"Honestly, it was very surprising to us," she said about Monster High. "We just noticed girls were into darker goth fashion."