Yuuri

Yuuri is a member of Duel Academy. He is cruel and ruthless with no care of other people's well-being and is very loyal to the Professor and will carry out his order without any question, going as far as eliminating anyone simply because he thinks they were interrupting his mission.

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He is the Fusion Dimensional counterpart of Yuya Sakaki (Standard Dimension), Yuuto (Xyz Dimension) and Yuugo (Synchro Dimension).

(Source: Yu-Gi-Oh! Wikia, edited)