Leo Akaba

Reo Akaba is an unseen character in the Yu-Gi-Oh! ARC-V anime and is the father of Declan and Reira. He is responsible for The Academia's attacks on the Xyz Dimension and the main antagonist of Yu-Gi-Oh! ARC-V

Etymology
"零" ("rei") means "zero" or "nothing", while "王" ("ō") means "king". The normal reading of Reo's name would be "Reiō"; however, it is read as "Reo" instead, so Reo's name is pronounced exactly like "Leo" in Japanese.

Biography
Reo was first mentioned by Shun Kurosaki when Declan first confronts him. For yet to be revealed reasons, both Shun and Declan consider Reo their enemy, with Declan insisting he is preparing Duelists to face and defeat Reo.