Yui Kanzaki/Episode Final

In an alternate retelling of the series, Yui Kanzaki (神崎 優衣) is Shinji Kido & Ren Akiyama's accomplice who is aware of the existence of the Mirror World and the Rider Fight.

History
In this alternate story, Yui and Shinji already met each other as a child as they promised each other to play again in the next day. But however, it didn't turn out well as Shinji didn't come out due to rain as she returned home. Saddened of what happens to her, Yui's mirror counterpart pays her a visit and accompanies her to play in the Mirror World. However things only getting worse as she will die when she returns. The mirror counterpart agrees to lend Yui her lifespan which will only last on her 20th birthday in an exchange for her drawings of the Mirror Monsters. Before returning, she visit Shinji (via mirror transportation) and plays with him for the last time.

In the present day, she locks herself in an abandoned room at an apartment with Shiro appears and celebrate her 20th birthday. When Yui finally dies, Shiro screams out of his failure and vanishes as the battle of Knight and Ryuga continues, they crashed into Yui's room, with Knight cancels his transformation as Ren was devastated with Yui's death. As Ryuga is about to finish him, he witness Yui's corpse and with Shinji (who was earlier duped by Ryuga himself) finally escapes as he realized that Yui never wanted anybody's life and rather leave herself dead giving Shinji/Ryuki a higher hope to defeat Ryuga.

Portrayal
Yui Kanzaki is portrayed by Ayano Sugiyama (杉山 彩乃).