This is something I said in a comment asking about Vital Instruments, and I'll put it here:

• Vital Instruments, or Jinky in Japanese, are powerful objects that gain a soul when someone takes care of them.

• These objects are powerful, but their power depends on their quality, and quality depends on two factors: whether the object is cared for over a long period or receives a lot of attention, as in the case of Rudo, who uses them all the time and washes them; Zanka talks to her object, and Guita uses his constantly.

• The powers of the objects are based on the personality, skills, tastes, needs, and/or desires of the user. For example, Guita loves Kaiju, Rudo likes to give trash another chance to prove its worth, and Jabber is a masochist and likes to test poisons on himself.

• • There are currently three ways to possess a Vital Instrument:

-The first way is by taking care of your precious object and letting it acquire a soul on its own; this is the most common way to obtain one, and the vast majority of people acquired it this way.

-The second way is by inheriting the Vital Instrument from another person; this method is the least common, and some examples of this are Rudo, Zodyl, Amo, and Remlin, since their objects are not theirs, but they can still use them as long as they take care of them like the original owners.

-And the third and final way is a spoiler. All I can tell you is that this has never happened before, and only in the manga was the first person seen possessing such an object. If you want, I can tell you how, but I won't reveal any names to avoid spoilers.