Bi-O is a playable character from Bust A Groove 2. Bi-O is Gas-O's father. Before he was turned into a zombie, he attempted to remove his son's mask, and even threatened him with an axe causing Gas-O to became enraged. Gas-O gassed his father with his acidic gas and immediately retrieved his axe. Bi-O was angered by this, as his face and body started to deteriorate. Without warning, his enraged son comes from behind him with the axe and stabbed his father in the head. Gas-O is later arrested after the incident, explaining his absence in Bust A Groove 2. Neighbors and those around him began calling him Bi-O due to his zombiesque appearance. Doctors could not restore his face and head to it's original appearance due to the axe being irremovable without causing further catastrophic damage. Bi-O's only hope was to play catch with his son, Gas-O, who is later arrested for what he did to him. In the end of his epilogue in Bust A Move 2 where he was guested by James Suneoka, the axe on his head was removed by the host himself as the axe gets into his head while it continues to bleed overtime.