Miu Shiunin

Sora's sister is an unnamed character in the Yu-Gi-Oh! ARC-V manga. She is Sora Shiunin's younger sister.

Biography
In the middle of the Action Duel between Sora and Yuya Sakaki, a photo of Sora and his sister flew from Sora and ended up on Yuya's hands. Yuya looks at the picture and asks Sora if the girl is his little sister. Upon Yuya's question, Sora started shaking and sheding tears, saying that he couldn't lose the Duel no matter what. He then explained that he has a sick little sister, but Reiji Akaba is taking her hostage and will kill her if he doesn't defeat Yuya. Sora then begged "Phantom" to let him win the Duel, with tears flowing from his eyes, making Yuya choose not to activate his Trap Card upon Sora's attack. However, after that, Yuri switched places with Yuya, calling Yuya soft, and declaring that he won't go easy. Sora tried to remind Yuri of his sick little sister, but Yuri yelled at him saying that he didn't care, and that they could both die for all he cared.