Ryōma Sakamoto functions as a supporting character. He commands a pirate organization engaged in maritime operations, with Maika Yurihara serving directly as his subordinate under this command structure. Details concerning his origins or personal history within the series' specific alternate timeline remain unexplored. His character also undergoes minimal development throughout the series, lacking significant evolution or explored motivations. Ryōma Sakamoto does not appear in any franchise spin-offs, OVAs, or movies. A planned 3D film reboot was indefinitely frozen after failing to meet its funding goal, preventing any expanded portrayal beyond the original series. His relationships with characters outside his pirate group, his role in the overarching Onigami mecha conflict, and his ultimate fate remain undocumented.