Dr. Hajime Akebono, grandfather to protagonist Akira Akebono, is a renowned scientist specializing in Battle Robot creation. He designed and constructed all robotic members for Team Akira, including the innovative Cluster System enabling Ryugu and Daigu to form the primary robot, Daigunder. His creations further encompassed the Animal Unit – Bulion, Eaglearrow, and Drimog – and the Dino Unit – Bonerex, Despector, and Trihorn. Bulion marked his first major Battle Robot achievement. A small maintenance robot, Beebot (or Sabuto), handles repairs and upgrades under his supervision, with stickers bearing his likeness placed inside the robots as proof of his craftsmanship.

His professional history features a significant past partnership with Professor Maelstrom (also referenced as Professor Deikun or Daikun). Together, they built DragoBurst and the Dragon Unit robots DragonFlame and DragonFreezer. This alliance fractured upon the revelation of Maelstrom's malevolent intentions, causing DragonFlame, DragonFreezer, and DragoBurst to rebel and flee to a space station. Following this schism, Hajime continued his scientific work independently.

Personality-wise, he actively encourages his grandson Akira's ambition to win the Titan Belt through Battle Robot tournaments and maintains a personal passion for travel. While typically operating behind the scenes, his foundational role in creating the team's robotic arsenal is crucial to their efforts, backed by his established reputation as a famed Battle Robot creator.

His character arc concludes with a reconciliation with Professor Maelstrom after the latter abandons his antagonistic path, resolving their earlier conflict. This coincides with the return of Maelstrom's robotic enforcers Ginzan, Tigamaru, and Rogamaru to his side.