Lady Tremaine

Lady Tremaine is Cinderella's wicked stepmother and an antagonist from Kingdom Hearts Birth by Sleep. Otherwise known as the "wicked stepmother", Lady Tremaine is mother by blood of Anastasia and Drizella. Using the poor Cinderella as a maid, she will do anything to ensure her two daughters' own success. She originated in Walt Disney's classic, Cinderella.

Kingdom Hearts Birth By Sleep
In Birth by Sleep, Lady Tremaine's role is exactly identical to that of her film role. Treating Cinderella as a house servant and showing no love towards her, the wicked stepmother does all in her power to see that her daughters are successful in life. She is upset by their constant sibling rivalry, also showing an extreme affection for her devious cat named Lucifer, despite the animal's cruelty to Cinderella's mouse friends.

After discovering the identity of the maiden that had won Prince Charming's heart at the royal ball to be none other than Cinderella, Lady Tremaine immediately locked the poor girl in her room when it came time for Anastasia and Drizella to try on a single glass slipper that had been left behind when the girl fled. Lady Tremaine's plot was eventually undone by Ventus, Aqua, and Cinderella's animal friends however, Cinderella escaping her stepmother's wicked grasp to become a princess.

Origin
Originating from Disney's classic film, Lady Tremaine served as a quiet, yet cunning antagonist. Doing all in her power to make Cinderella's life miserable for the good of Anastasia and Drizella's own welfare, the wicked stepmother was often seen pampering her spoiled cat, Lucifer. She used her conniving and trickery when the Grand Duke came to her estate with a single glass slipper that would announce Prince Charming's wife, having her birth daughter try the delicate footwear and then claiming there was no one else to try it on when both girls didn't fit. However, thanks to Cinderella's many animal friends, her plans failed, the maiden that was once a servant going off to the castle to become a princess.

Trivia

 * Judging by Ven and Aqua being the size of the mice while in the wicked stepmother's house, Lady Tremaine could be the very first Disney antagonist featured in the Kingdom Hearts series not to be a boss.