Madonna

Madonna was supposed to be a love interest for Sonic back when the original game was still in development. She was a blonde haired skinny human woman in a form-fitting red dress and was actually going to be Sonic's girlfriend. However, she was scrapped from the final game, along with other things that were to be in the plot (like Sonic being in a rockband).

Description
She was supposed to chase Sonic around like Amy Rose does in current games. She was first designed by Hirokazu Yasuhara, as a very attractive woman who would chase Sonic. She was later removed by Madeline Schroeder, her reason for removing Madonna was that she wanted to "soften" Sonic for children and foreign countries, because she thought it was too "Japanese". Madonna can also be considered the equivalent of Pauline in the original Mario game, Donkey Kong.

Trivia

 * In an episode of Adventures of Sonic the Hedgehog entitled "Sonic is Running", the look of Sonic's female disguise to fool Robotnik was similar to Madonna, but only the hairstyle was different.
 * Also in episode "The Mystery of the Missing Hi-tops", one of Harry the Hucker's ties for sale shows blond woman in a short red outfit which closely looks like Madonna.
 * Additionally, Breezie seems to resemble a hedgehog version of Madonna because both of them wear the same clothes.
 * Madonna is generally based on the real-life performer with same name.
 * Head writer Ian Flynn as revealed that Madonna will appear in the Sonic the Hedgehog comic series and its spin-offs, albeit "not in any way [we'd] expect."