Hideyuki Kagawa is a major antagonist in Kamen Rider Ryuki.
He is a professor/scientist at Seimein University who used to live a normal life until stumbling upon the notes of a student named Kanzaki Shirou.
This led Kagawa to embark upon a delusional quest to stop Kanzaki from giving his sister Yui more life. Viewing the girl as a monster due to being a mirror being he soon created a cabal who wanted to "save" people from this.
Biography[]
Kagawa was a normal and humble man that ended up staring his career as a professor at Seimein university, who at one point bumped into Kanzaki Shirou and noticed his schematics for the rider system. Although getting a glimpse his mind instantly saved what it said, remembering it enough to create the alternatives. Through the years he discovered more about the mirror dimension and got Toujo and Nakamura his students to help him seal the mirror dimension.
He had a family too a wife and young son who he concealled his activities from for their own safety. While doing so he told his students that they would be heroes but have minimal casualties. Yui Kanzaki was investigating her brother's old lair where she found Kagawa who told her that nothing was happening here, before stopping her when she got to the mirrors. Shinji or Kamen Rider Ryuki thought they were potentional allies since they wanted to destroy any more of a chance the mirror world had to erecting chaos.
Soon though Shinji didn't want to affiliate with them since they seeked to slay Yui preventing her from unleashing mirror monsters into our world. Nakamura at one point wanted to destroy the mirrors but even though the former's colleagues were killed by Shirou's action, Kagawa wasn't out for revenge just simply to save Earth. Toujo soon ended up killing Nakamura for what Kagawa was growing concerned off.
Later Ren found him and they fought, with Kagawa explaining his intentions. Revealing he wasn't a tyrant and just wanted peace. Being even against killing Shinji earlier he refused to slay Ren. Although Kagawa had his philosophy challenged when Shirou told him to stop being an alternative or his family would die. They survived thankfully but later he used this to show Toujo compassion (though he ended up hurting Toujo with many of his speeches psychologically, which just made him worse and worse, with Kagawa barely apologizing for it).
This would be to no avail when he was about to destroy Yui, Toujo turned on him and killed him.
World Of If[]
In the alternate ending of Kamen Rider Ryuki, Kagawa's past is explained in a better way: ever since he was a child, he had a complicate relationship with his parents, who always pressured him into becoming the "better version of himself", due to this, he had constant arguments with them.
One day, when he was still a student, he saw a Mirror Monster abducting and killing a child, and while at first, Kagawa tried to save the kid, he ended up backing up and leaving the scene out of fear. Due to this, he promised himself to exterminate all Mirror Monsters to finally be able to overcome his fears and become a Hero. It is possible that this version of Kagawa didn't had a stable romantic life compared to the series one (specially since Kagawa implies through dialogue that he recently ended up getting divorced by his wife for unknown reasons).
Eventually, he would realize that Shiro Kanzaki was behind the creation of the Rider War, due to this, he created a cult full of copies of himself called 'The Alternatives', some of those copies of him stole weapons from the area (from close range swords to long range guns). Shortly after that, Kagawa and his cult would find Yui Kanzaki and in an attempt to kill her, he accidentally ended up attacking Ryuki, causing the latter's demise. A shocked Kagawa couldn't believe Shinji was willing to sacrifice his life for someone like Yui, and when he says that, Yui asks him for something.
At the end, it is revealed that Yui asked Kagawa for his deck so she can use it to transform into another Alternative and confront his brother in order to stop the war and all of the killing, a hesitating Kagawa ends up accepting Yui's proposal and gives her the Advent Deck. Unfortunately, this would end up being in vain, since Yui didn't managed to convince her brother in time and she ends up getting killed by collateral damage, due to this, a now disturbed Ren (who was being controlled by Shiro) became Kamen Rider Odin and decided to repeat the Rider War over and over again, Causing the death and torture of all of the Riders in the place (Including Kagawa).
Equipments[]
Gallery[]
Hideyuki Kagawa[]
Alternative Zero[]
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 Villains
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Kamen Riders Mirror Monsters Kagawa's team Other | ||