For three years schoolboy Akira has been saving up for a computer. When a model 9821 goes on sale he runs to the store only to find it sold out in five minutes. Discouraged, walking home he discovers a suspicious looking man in an alley who happens to have the computer he was looking for and he bought it instantly. When he opens the box he only to find that he did not purchase a 9821 but a 2198, a super-advanced bio-mechanical computer girl named Mimi and willing to be his slave and she called him master. But another  masterless” Mimi ” computer goes rogue and hunting Mimi and she wants to eliminate the good ” Mimi”.