Ellen Mira Mathers is the secondary antagonist of the Date A Live series who is first introduced in Volume 5 alongside Sir Isaac Ray Pelham Westcott. Ellen is a beautiful young-looking woman with light Nordic blond hair, purple eyes, pale skin and a slender body. She normally wears a black suit, but manifests a platinum Wiring Suit and CR-Unit in battle. Ellen's height is stated to be 160 cm, and her three sizes are B86/W60/H87. Ellen is usually calm and analytic, especially when around Westcott. However, during battle, her true personality is revealed. Ellen is actually very battle hungry, as shown when she chose to fight Tohka directly instead of just capturing her and later stated her disappointment when she easily defeated her in her limited release Astral Dress. Ellen also dislikes teaming up on a single opponent. Ellen doesn't seem to care about weak people, quickly losing interest in Tohka after she defeated her during their first battle, and not caring about her own comrades because they couldn't keep up with her. However, Ellen is able to acknowledge and praise others their ability. Also, she doesn't seem to allow her battle loving nature to control her too much, putting her job first. Ellen is very prideful about being "The World's Strongest Wizard". According to Westcott, Ellen made a vow to never lose to any opponent, even if it is the atrocity that kills the world. She appears to be completely convinced of her own invincibility, claiming no one in the world can defeat her and claiming without a doubt that if she weren't wounded she would have won against Tohka in her Inverse Form. She also believes that she has no faults, seemingly unaware of the fact that without a Realizer she is in fact very clumsy and physically weak, as stated by Mana. She also has a huge ego that twists some things so it will make her seem strong, claiming she defeated Nia while in fact she only caught her off guard through a sneak attack. Ellen seems unwilling to accept her losses, after her first attempt to abduct Tohka failed, while accepting full responsibility for it in front of Westcott, she internally blamed James A. Paddington and the students of Raizen High School for the blunder. Ellen also felt humilated when Shido, controlled by all the Reiryoku in his body, condescendingly flirted with here while easily resisting her Territory, causing her to swear vengeance. Ellen also has a habit of continuously stating her title to others. However, despite all of this, Ellen has also shown the qualities of a typical girl. While normally calm, when she is annoyed she is quick to get angry over even very small things. She can also get embarrassed, as seen when Westcott teases her. Also, when confronted by an out of character Shido that tried to flirt with her, she became shocked and embarrassed to the point of trying to use her Territory to separate him from her. One year after the final battle against DEM, Ellen has lost her memories of everything involving DEM and Westcott. Consequently, Ellen's new dominant personality is much more meek and easily prone to embarrassment from just being stared at. She is also susceptible to headaches whenever she hears the word "strongest" now.