|“||I was… worried about you. Ever since you've been kidnapped by those DEM guys… but I'm glad… I'm really glad. Mio ......Didn’t that person help you out?||„|
|~ Shido to Mana|
Corrupted Shido Itsuka, also called as The Beast of Demise or Shido Takamiya is an antagonistic evil counterpart of Shido Itsuka (heroic version) introduced in Date A Live: Itsuka Disaster and is the final villain on light novel Volume 13. "Corrupted Shido Itsuka" is considered an evil version of Shido Itsuka when he demonstrates his hunger for chaos and destruction in order to find and kill all the officers of Deus.Ex.Machina Industries. Corrupted Shido apparently seeks revenge in killing Isaac Ray Peram Westcott, the twisted individual who kidnapped Mana Takamiya, Shido's biological sister, when they were children. Isaac Westcott also turned Mana into a assasin Wizard; which led Shido to dark side.
Same for both of Heroic and Villainous appearance
Shido has all the looks of an average young man in high school. With blue hair down to his neck, amber brown eyes, and has straight hair and bangs. He is usually seen wearing his school uniform. His height is stated to be 170 cm in the anime. During the events of Miku Lily, Shido crossdresses as a girl in order to interact with Miku, and he disguised himself as his alternate identity, Shiori Itsuka. During the time he crossdressed, he was seen with long blue hair, and he wore the standard female Raizen High School uniform. He also had a hair clip, which seemed to be a flower of some sort.
Working for both of heroic and villainous version
Abandoned by his birth mother, Shido was adopted into the Itsuka household at a young age. Five years ago, an incident caused Kotori Itsuka to become a Spirit due to a misunderstanding on her part and was tricked into becoming one by Phantom, but neither of them can remember anything about that incident until Kotori personally used her powers again five years later, which awakened those memories in both of them again. It was discovered that Shido possesses the ability to seal the powers of Spirits around the time Kotori became a Spirit, but it is not known how he got it in the first place.
Before the incident, Shido seems to have met Origami Tobiichi, who lived in the same district, since she claimed to know him when they first met at the school while Shido couldn't recall anything about their meeting. During the events of Tobiichi Devil, it is revealed that this is because Origami met the future Shido, who traveled back 5 years to the past using Kurumi Tokisaki's <Yud Bet> and eventually shrunk his body with Natsumi's power to find out the reason for Origami's Inversion. After saving the 11-year-old Origami from being crushed by a part of a burning building, Shido comforts Origami, who, at the moment, on the verge of despair. He told her that she can give anything to him as long as she doesn't feel despair in which Origami replied that she will give him her tears, smile, happiness, enjoyment and everything with the exception of her anger towards the spirit who killed her parents. At some point, Isaac Ray Peram Westcott and the Deus.Ex.Machina Industries kidnapped Mana Takamiya from his arms and tortured her in order to become one of the strongest Adeptus in the world. Shido could not protect her and and kept hatred for DEM Industries for many years, however, when the memories of Shido went out for unknown reasons, Shido forgot that Mana was kidnapped. He only remembered again when the power of the Spirits woke up his past memories.