Rio Kastle

She is an unnamed character appearing in the Yu-Gi-Oh! ZEXAL anime and the sister of Reginald Kastle.

Biography
She once Dueled IV who operating under the orders of Tron. He played a card, "Flaming Hell Blessing", that set the surrounding area on fire. She was critically injured in the blaze, though IV carried her to safety, his face being scarred in the process. She was hospitalized. In order to help his sister, Reginald entered the National Duel Circuit and made it to the final match against IV. In the break room, IV set his Deck up to fall on the floor, causing Reginald to see some of its contents. This caused him to be disqualified.

Trivia

 * When Yuma faces Shark in episodes 61-62, Shark's sister might be involved in saving Shark from the influence of Tron, and Shark Drake.