Ai is straightforward and direct. Often boastful and self-centered, mostly impulsively acting based on how she feels like with little concern over consequences, her bossy nature tends to prefer her taking control of situations and making decisions she chooses to make rather than following others, which tends to be at odds with her conception as a “tool”.

She is easygoing, carefree and abrasive, displaying full confidence in herself and presenting to others with determination and dignity. On the other hand, she is also quite lazy and self-indulgent, disliking having to work, making her a somewhat selfish and unconcerned person. Despite this, Ai tends to fight for goals and ideals she considers dear to herself, often at the expense of herself. The sort of person to say they don’t want to get involved in a situation, only to then get involved in a situation because they feel that it is “right” for them to do so.

Tsukumogami Transformation: The ability to change one’s composition. Ai’s body is an amalgamation of a thousand blades, however, this ability lets her take on the mask of a “human”. It is a perfect impersonation of a person, having the same biological functions as a normal human, from the need to eat to the need to use the bathroom and other such things. However, she has the ability to change into her true form as a blade as she chooses. Ai can also turn into a blade to be used by another, or partially transform select parts of her body into weapons, or graft other weapons to join this collective. Regardless of her chosen appearance, she is still a “weapon” at heart.

Metal Control: The ability to freely control metallic objects. From simple touch, the shape, structure, and strength of a metallic object can be edited and changed to suit Ai’s needs, from grafting a shield of metal to their arm or changing the shape of a blade during combat to gain an advantage from an unsuspecting opponent. Given that they are themselves a mass of blades, this affects her as well.

Inanimate Object Communication: The ability to freely communicate with inanimate objects. To discern the residual “feelings” leftover inside of an object into a “conversation”. Through the use of this ability, Ai can understand aspects of the owner of the object or create a comradery between discarded “tools” like herself.

Knowledge of Swordsmanship and general Fighting Ability: Due to her status as a weapon, Ai is skillful in the application, tactics, and techniques of battle. She is also able to give her wielder the ability to use these skills without them needing the knowledge to utilize her effectively if so she chooses, as well as transfer information between herself and her handler instantaneously.

Does "herself" count as a piece of equipment? If not she carries around one of her blades at her side at any time and is very proficient at using such.

There was once a blacksmith, young and with much ahead of him, who helped all those in his village. From basic tools to appliances, the man was beloved and revered by those in his community and afar, often people coming from far and wide to take shop of his wares.

One day, on a trip to gather ore from the mine, he returned to find his village in ash. A youkai had destroyed his village, reducing it to no more than ash, and killing all who he had known and smiled with.

Outraged by this, the once pacifist blacksmith chose to create weapons, something he had refused to make before. He kept smithing, and smithing and creating better and stronger blades to fell the demons who had taken the lives of his fellow man with.

Who had killed his loving wife and son?

Who had destroyed all that the blacksmith treasured and wished to protect?

However, before he was able to use these weapons he had created, the blacksmith had decided to abandon his quest for revenge, leaving the weapons without purpose and to rust. Filled with the regrets of her master, the Tsukumogami was created. Nameless and without a face, the wretched abomination of metal that was the body of the bestial creation roamed the countryside, trying to find peace from its creation.

However, eventually the creature had found upon her creator, now an old man hardly suited to fight with. Asking her master why he had abandoned her, her master only responded with:

“If I were to kill youkai who had nothing to do with the destruction of my village, then would I be that much better than those who had taken the lives of my kin long ago?”

Then was all that the nameless blades have done been all for nothing? Outraged by this answer, the nameless blades chose to end her creator’s life. In the old blacksmith’s final moments, he spoke out the final words of his once beloved wife who had been the driving force for the creation of these blades, dying with a satisfied smile on his face.

“Ai.”

The blades knew not what to think. They had only had to kill what was before them before, hardly having to consider the ramifications of their actions, but for whatever reason, the words of her creator bothered the blades. The blades wept. They wept for the old man, now dead. They wept for those who they had killed on their journey, most of which were undeserved anger.

But most of all … the blades wept for themselves.

Taking upon the name that the blacksmith had said as his last words, the nameless blades, now “Ai”, decided they would atone for their actions. They would try their best to become human. To finally understand why her owner had given up on his quest for revenge, and to try to be a force for protection rather than solely an instrument of destruction.

However, it was too late for Ai, for she had been sealed for her transgressions, only recently awaking from her several hundred-year-old nap. Who sealed her and why she was sealed seemed to have been lost on her, and she hardly remembers anything aside from her name and the fact she is a weapon.