Shinki (神器) are spirits that gods use for various tasks and purposes, having the ability to transform into items or weapons. They are also called Regalias in English. Other types of Shinki include, Sacred treasures, Sacred weapons, and Sacred tools.
A shinki is made from the Loose Spirit of a dead human (死霊, shiryou). The term “loose spirits” usually refers to the wandering souls of people who died from being murdered or killed in accidents. In the eyes of the gods, people who died due to these causes deserve a second chance, since they originally still wanted to live; this is probably why these souls are chosen to become shinki.
Shinki retain the looks of their human bodies when they died. Since most of the loose spirits die at young ages as humans, it is common for shinkis to look young. Yukine, for example, looks like a teenager, Mayu looks like a woman in her early twenties while Daikoku looks like a man in his late twenties/early thirties.
Before a loose spirit is taken in as a shinki, the spirit must not be corrupted in any way, therefore being a pure spirit. A spirit can be corrupted and become unusable when it’s attacked or possessed by phantoms (partially or fully). A spirit will also be possessed if the human died due to committing suicide because they chose to die willingly and the evil inside takes over. If a soul is attacked and gets even slightly impure, its item form will become partially or entirely unusable (e.g. dull, torn, broken, etc).
Creation of a Shinki
When a god sees a loose spirit and wants to take them as their shinki, the god must give them two names: one for the human form, and another for the vessel form. The Kanji character of the vessel name will then be imprinted on the soul’s body, marking the ownership for the said spirit. It should be noted that many of the Kanji used to name a shinki to use the older form or an alternate form of the supposed characters, or uses the on'yomi version of the character. Therefore, watchers and readers may notice that some of the Kanji imprinted on the shinki’s body look different than the actual character. Their imprint also contains the god's greatest secret, in which details regarding their past life, including name and cause of death, are sealed. When the creation process is completed, the god immediately becomes aware of the details of the shinki's life.
The first pronunciation is used in the shinki’s human name, and it is based on the native (kun'yomi) reading for the Kanji character. Using this name changes the shinki into its human form. Usually, another Kanji character of the god’s choice is added to the first name to become the shinki’s name as a person. This Kanji character serves as a shinki’s “family name” or "clan name", and a god can have one or more family names as desired. For example, Yato’s is “ne” (音), Tenjin’s is “yu” (喩) and Kofuku’s is “dai” (大). Bishamon has two “family names” - “ma” (麻) for Kazuma and “ha” (巴) for the rest of her shinki.
The second pronunciation is the vessel name, and it is based on the Sino-Japanese (on'yomi) reading for the said character. Using the second name changes the shinki into its item, or weapon form. Usually, the character “ki” (器, vessel) is added to the end of the second name to become the shinki’s name as an item/weapon.
A shinki’s vessel form varies from an owner god to another, such as weapons, animals, clothing, or accessories. For example, Yukine becomes a blade, Mayu is a smoking pipe, Daikoku becomes a fan, Kazuma an earring, Kuraha a lion, Kinuha a whip, Tsuguha a set of provocative clothing, Karuha and Kazuha as guns, etc.
Responsibilities of a God to a Shinki
After taking a shinki as their subordinate, a god is to provide basic necessities for the shinki (shelter and clothing to be precise; other things like food, drinks or entertainment are optional). The god is also to train a shinki if the shinki is still new.
Aside from basic necessities, the god bears the responsibility of taking the burden of all the emotions the shinki has, and the sins it commits. The burden the god bears is in the form of stabbing pain on the back of their neck. Other than stabbing pain, the area of the god's neck will also become infected by impurities, called blight. If the shinki continues to commit sin and no action is taken against it, the blight will spread all over the god’s body, causing the god to slowly degrade and die.
A god's greatest secret is their shinki's name and past life. They must never tell their shinki details about their former life. Doing so will allow their shinki to remember their past and how they died. The trauma and negative thoughts turn the shinki into a karma ayakashi. At this point, the shinki is beyond redemption, and a purification ceremony will not work. The god's only option is to slay the karma.
Responsibilities of a Shinki to a God
A shinki is responsible to obey their master at all times, control their emotions, and also control themselves from falling into temptations that lead to committing sins. This is because the name bestowed onto them is actually connected to the god’s life, and therefore any kind of disturbances - intense emotions, sins committed, death - will be sensed by the god in the form of stabbing pain, or even blight.
It would be assumed that once a soul becomes a god’s shinki, the god and the shinki become one in mind and body, and the pain should go in both directions. However, that is not the case; the pain will only transfer from the shinki to the god owner, because of the shinki's previous status as a human. Humans' lives are affected by the concepts of good and evil, sin, heaven, and hell. Gods, on the other hand, are not restricted by these concepts, and therefore are free to do as they please.
Once a god is stung by their shinki’s thoughts or acts, appropriate action should be taken against the offending shinki. Usually, a ritual called a purification (or ablution) ceremony is performed against the shinki, making it confess all of its sins. Depending on the severity of the offense, the shinki will also have its name released and will be banished, or worse, killed by the owner god. However, the decision to release the shinki’s name and banish it is up to the owner god. For example, Yato didn’t release Yukine’s name, even though Yukine nearly killed him with his sins; Tenjin, on the other hand, released Miyu’s name and banished her on the spot when she cut her own wrist once.
It is also unethical for a shinki to bow down in front of a god when it is already serving another. This action is considered rude towards the god it’s supposed to serve.
In the manga, a shinki can evolve from its original form to a better form. A shinki with this characteristic is called a blessed regalia (祝の器, hafuri no utsuwa, meaning a blessed vessel) or a hafuri vessel. However, becoming a blessed regalia is not as easy as it looks; it involves protecting the god with the shinki's own life, risking their name to be taken away. It is said that a shinki can only become a blessed regalia in special situations. Once a shinki becomes a blessed regalia, the new form will last forever, and it also grants a power upgrade in vessel form.
So far, there are only three known blessed regalia in Noragami:
- Kazuma evolved from a black nail earring into a sakura-shaped earring, due to the sacrifice of his shinki clan in order to save Bishamon, risking his life and status in the process.
- Nana was previously a blessed regalia. For Bishamonten, she turns into a full set of clothing, including a skirt, bindings around the breasts and a mask that covers Bishamonten's eyes. She also becomes a sword with a curved blade tip. It is unknown if this was also her form when she was with her original owner god.
Releasing a Shinki's Name
When a shinki wants to quit their job and serve a new master, it is common practice for the god owning it to release the name given to them. By writing the shinki's Kanji vessel character and saying, “I release you”, the name imprinted on the shinki will disappear, making them available for another god’s use. A shinki’ released once cannot be given a second name by the same user. The abilities obtained as the god’s shinki will also disappear. However, it is unknown whether in this form the shinki is still able to use borderline.
When the shinki is given a new name under a new master, it is possible for the shinki to take a different form, thus having different abilities. The best example for this case is Mayu; as Yato’s weapon, known as Tomone or Hanki, she takes the form of a dagger; however, as Tenjin’s shinki, known as Mayu or Shinki, she takes the form of a smoking pipe.
A shinki’s name can also be released by force; usually through the purification ceremony, or when the shinki is killed. However, these methods cause pain to the gods owning them.
There are cases where a shinki has more than one name on its body, indicating that it’s owned by more than one god. The shinki with this characteristic is called a stray (野良, nora). A shinki becomes a stray when a god gives a new name to it while it’s still owned by a previous master. One known stray is a shinki merely known as Nora. In the manga, aside from Nora, other known strays are Bishamon's shinki Kugaha and the majority of Ebisu's shinki. Kazuma later becomes a nora in Chapter 78 of the manga.
It is revealed that strays are feared due to the fact that they own more than one name, and it is due to this reason that they are despised by the gods and shinki alike. A stray cannot be bound using any technique that links to their names easily; unless all names of a stray are known, other shinki cannot use bind or any other immobilization techniques. Strays can also change hands from one god to another, should their names be called, literally betraying the master they were serving at that time. Killing the strays might also end up backfiring, as all the gods linked to a killed stray will feel the great pain of losing a shinki.
A Shinki's Lifespan
A shinki’s lifespan is still unknown; however, they can live for as long as hundreds of years. Although they can live for a very long time, a shinki can easily die like any other living being, through ways such as being killed; however, it is unknown whether they can die from natural causes. When a shinki dies, their name disappears and the owner god will sense it.
Known cases of shinki deaths are all of Bishamonten’s shinki under the clan name Ma, except for Kazuma. They were all killed by Yato using Hiiro (Nora). Other known deaths are most of Bishamonten's shinki under the Ha name, by Kugaha's masked phantom.
A God's Greatest Secret
A god's greatest secret (神の秘め事, kami no himegoto) is a shinki's real name from when they were human. When a god names a shinki, the name bestowed by the god seals the memories of the shinki's human life, including their real name. The god sees these memories upon naming the shinki and must keep them a secret. If a shinki learns their real name, the posthumous name given by the god is destroyed, and the shinki becomes instantly corrupted by the memories of their own untimely death. At this point, the shinki's soul is unsalvageable, and the only thing that can be done is to kill it.
Gods have a strong instinctive aversion to revealing any information regarding a god's greatest secret; however, they are not entirely physically incapable of it, as demonstrated by Nora goading Yato into revealing Sakura's real name to her, despite his internal objections. A god's greatest secret can also be revealed by Father's technique Liberation while wielding Nora, as was done to Tsuguha.
Nora herself seems to be immune to her god's greatest secret, as she is able to discuss it, invoke it, and witness it to no ill effect, whereas it is stated that if normal shinki becomes aware of even the existence of the secret, their curiosity about their past becomes all-consuming until they degenerate. However, the only one that knows about her real name and how she died in the first to give her a shinki name, in this case Kouto Fujisaki.