In the not too distant future, mankind fights over relics from an ancient civilization called O-Parts, each of which contain incredible powers. Jio is a young boy with a tragic past who only trusts one thing in the worlds: money. Little does he suspect that he is also a very powerful O-Parts Tactician (OPT). With his partner Ruby, Jio embarks on a dangerous quest to acquire as many O-parts as he can. The government of Stea is on the hunt for a pair of rogue O-Parts users. Armed with a high class piece of weaponry, this devious pair of lawbreaking brothers is ready to hit Stea's special squad with everything they have. More of Jio's past is revealed.