The Chief of Staff of the Royal Army of Edolas who serves under King Faust.
Even though Byro's origin story is not reveal, he is the chief of staff in the technology/ magic department for King Faust and his assistant is Coco.
Byro, who is created by Hiro Mashima, has no information regarding any inspiration used by the author to create him. He first appears in Fairy Tail volume 21 and episode 80. His Japanese voice actor is still unknown.
Byro first appears when Hughes, Sugarboy, and Erza Knightwalker are talking about the lacrima from Earthland. Byro makes a comment about Knightwalker's Fairy Hunter reputation. Sugarboy reassures Byro that they will eventually defeat the rebels. Byro laughs in a creepy fashion which is interrupted by Pantherlily. According to Knightwalker and the two captains, Pantherlily is upset over the recent military buildup. In a meeting with Faust and other captains except Knightwalker, Byro and Coco discuss about the Earthland mages and their magic. When Hughes complains about having to execute Lucy (a waste of magic), Byro tells Hughes that they cannot extract magic from Lucy, but they can extract magic from the Dragon Slayers. Byro explains that the Dragon Slayers are not human nor dragons. After the meeting is adjourned, Faust orders Byro to complete the magic extraction of the two Dragon Slayers.
During the events of Code ETD, Byro is underground and is busy extracting magic from Natsu and Wendy. As he finishes, he heads off to Faust to hand over the key. Despite Coco's resentment over sacrificing Pantherlily, Coco steals the key. Byro tries to change her mind, but Coco runs. Before Coco could get away, Faust shocks Coco's feet. Byro chases after Coco into the amusement park.
Over at the amusement park, Byro chases Coco who bumps into Lucy Heartphilia. Misunderstanding Coco, Lucy prepares to defend Coco from Byro. Lucy summons Taurus to attack Byro, but Byro defeats him easily with the Flame Liquid. He immediately attacks with Storm Liquid. On the rebound, Lucy summons Virgo who sends Byro down into a hole. Suddenly, Byro ingests Octopus Liquid to transform into a giant, purple, octopus monster. Byro sends Lucy and Virgo flying. After Virgo hands Lucy her new whip, Lucy grabs Byro's tentacles and slams him into the ground. Before Byro can get up, Natsu punches him with Huges in a fiery process. Byro lays unconscious while the floor dissolves. Coco struggles to free Lucy who is stuck under Byro. Byro is seen again with Hughes and Sugarboy as they talk about how the effects of the leaving magic can change Edolas forever.
In episode 93, Byro, Hughes, and Sugarboy have an extra conversation that is not in the manga. They talks about how the effects of no magic can change Edolas.
Byro reappears in episode 130 and he appears much younger and taller than his edolas counterpart. He also appears standing on top of a giant octopus.