WMG / Noragami

Per wiki policy, Spoilers Off applies here and all spoilers are unmarked. You Have Been Warned.

Hiyori can detect gods by smell because she wants to eat them.

Yato described her as something like a half-ayakashi, so is not impossible that why she says that they smell "good" she actually means delicious, like a complete ayakashi would; she just hasn't noticed yet, or she is consciously ignoring it.

• The manga seems to imply this as well
• Maybe a nice fragrance that is both a flavor and a scent (e.g. steak or bacon can only be a smell that induces hunger, but green apples or vanilla are fragrances as well as food.) Or a tea smell (green tea or Earl Gray).
  • Confirmed in the arc starting in chapter 50. When she nearly became an Ayakashi, she took bites out of Yato.
• Half-busted. It is shown later in the manga that Hiyori's ability to see and interact with Gods and Shinki is something passed down through her family. Her brother and grandmother easily see Yato and Yukine when they're at the grandmother's house and Hiyori's mother can sense when they're in the house, even if she can't see them.

The real, real reason Kugaha wants Bishamonten to die and reincarnate:

He's actually a lolicon.

Yato's obsession with getting a shrine is actually about escaping his father

• Yato has revealed he can't stand up to his father because his father is the human whose wish caused him to come into existence, so if his father was wiped out, Yato himself may also cease to exist. Because a god's existence is tied to his believers, Yato is determined to build up enough of a following that he will always be remembered by someone other than his father so that he can safely remove his father from the picture and still continue to exist without having to grant his evil wishes.
  • When Hiyori gives him the mini-shrine, he says that if his father found it he would destroy it, indicating that his father is actively against his independence.

Hiyori's tail will be cut and Yato will revive her as a shinki

• However, this would mean that Hiyori would lose all her memories of her previous life, and Yato would not be able to tell her about who she used to be. If the above WMG is also true, it would also prove problematic for Yato as other gods and shinki don't count towards a god's set of believers, and Hiyori is currently the only human besides Yato's father who believes in him on a regular basis.
  • Confirmed in the most recent chapter.

Yato will die, but thanks to Hiyori's belief in him will reincarnate

• Yato and his father will mutually annihilate one another, but Hiyori's belief in Yato will cause him to reincarnate. However, Yato would reincarnate as a child and have no memory of his past life, and it would be up to Hiyori and Yukine to raise him properly this time instead of the violent childhood he had under his father.
  • Supporting that theory it has been stressed that Gods cannot change their nature and their nature is formed by those who create them. Yato's nature is to cull the herd. That would seem to make his goal to be a god of fortune impossible. Unless the member of the herd he chooses to cull is his father. If Yato gets taken out himself in the act he will be revived. Normally reincarnation doesn't change a God's nature but Yato might be an exception to that and here is why. Right now Yato is in the unique position of having exactly TWO mortals believe in him. But their VIEWS about his NATURE are totally contrary to one another. Before if Yato were to die and be reborn his nature would stay the same, as he would be resurrected by people or in this case A person believing that he culls the herd. But what happens if when Yato dies that person is dead and replaced by a person who belives Yato is a God of Fortune? If I'm correct he will be reborn as THAT person sees him. A god of fortune.

Yato will be forced to cut ties with Hiyori in order to save her.

• it's constantly brought up as the only way to cure her condition and it's also something Yato actively avoids doing because he doesn't want to lose her. But if Yato's father's plot to corrupt Yukine fails, whose to say he won't go after her? He's already tried ruining her life by destroying her father's career, and her connection with Yato ticks him off too. He could easily harm her because she's powerless in her human body and has a glaring weakness out of her body.

Hiyori as a Shinki weapon

• She would be the type to transform in to a mount. She will become a large feline big enough for Yato to ride into combat, similar to Kuraha.

Yato and Hiyori are aware of their romantic feelings towards each other but refuse to act on them.

• Everyone Can See It. But due to the issues that would rise in a human-god relationship, they both cope with their feelings by either denying it (Hiyori) or acting overly affectionate (Yato).

Amaterasu is a puppet ruler.

• First and foremost there was that scene in the manga where a goddess that is strongly implied to be Amaterasu shows up at the end of the Ebisu arc to tell Hiyori and the rest about the God Call. Yet she calls herself no one important, as if she feels guilty for this whole affair.
• Also let's look at Japanese history. Most of time the Emperor was a puppet ruler and someone else held the real power. It was easy to do this because the Emperor was kept separate from everyone as it was said that the divine must be kept separate from mortals. (according to legend the Emperor was descended from the Sun Goddess, Amaterasu) this meant the real power was with whoever supposedly spoke in his name.
• Amaterasu herself, along with Tsukuyomi and Susanoo are called the three great kami (gods) who were basically to the gods what the emperor was to mortals. It is possible that Amaterasu is kept separate from the rest of the gods so she can be used as a puppet ruler. One must wonder why we haven't seen her at the council of the gods when you would think she would be presiding.

Yato is actually Tsukiyomi.

A pretty elaborate theory based on numerous observations in the manga and historical japanese lore:

• To begin with, Daikoku once comments that it's a bit puzzling that a god as minor and unknown as Yato has been able to survive for as long as he has. While Yato himself theorizes that his father is his only strong, consistent tether to existence (before Hiyori, anyway), the fact that when gods reincarnate they start off as blank-slate children brings the possibility that Yato is actually the reincarnation of a famous god with many believers, such as Tsukiyomi, but somehow ended up in his father's care where Yato himself was raised to believe otherwise.
• If "father" really is the one who created Yato, it seems a bit suspicious that he is so dead-set on reining in and controlling Yato as he is now instead of just outright killing him and starting over from a reincarnation. It could be said that he doesn't want to waste the centuries of conditioning he's already put Yato through, but if Yato is actually supposed to be another God, that would also serve as explanation; because killing him would cause him to be reincarnated at his "true" shrine and away from his father's manipulative influence.
• Hiyori Iki is the first person to give a shrine to Yato. The Iki clan is the first family to offer a shrine up to Tsukiyomi.
• Tsukiyomi is the shinto diety of the moon. Yato's anime theme song is "Tsukiyo no fune" or "A boat in moonlight" and is often showed with the moon (motif). Also, when Yato was summoned by Hiyori out of Yomi, the moon is shown on the very next panel.
• Amaterasu, the sun goddess and the highest exalted deity in Japan, somehow knew who Yato was and seemed to have a special interest in saving him from the underworld despite the fact he's supposedly such an unknown god. Tsukiyomi is both Amaterasu's brother and husband. Perhaps when Amaterasu asked Hiyori to call out his name, she meant "Tsukiyomi" and not "Yaboku". Since Yato believes his real name is Yaboku, he'll respond to that name, but that doesn't preclude he has another one, since gods can have multiple true names.
• The first kanji in Yato's name is the kanji for 'night'. One of the alternate spellings of Tsukiyomi's name also contains the kanji for 'night'.
• Tsukiyomi is highly associated with water, and Yato himself also seems to have a water motif. When Yato first names Nora as his shinki, the fact she has water powers in addition to her katana form seems to visibly pique Father's interest. Yukine is potentially a reference to this too given that his name means "snow", ergo, frozen water.
• Yato's ability to cut ties seems to be, if not rare, completely unique to him. Tenjin specifically seeks his help with certain jobs because of this ability. Tsukiyomi is supposed to affect the bonds between humans.
• Yato is frequently referred to as a 'God of Calamity' because of his infamous past of taking on and granting violent wishes. However, Tsukiyomi, after killing another god, was also dubbed a 'God of Calamity' in mythology. Tsukiyomi also seemed to disappear from all mythology after being appointed in taking care of the night from his father, Izanagi.

Like Izanami, Izanagi will be completely immortal

• In his case as long as even One other God Exists, so will he.

Father is Izanagi

• Both Izanami and Izanagi were "mortal" gods, both human and divine, they were the first humans, the founders and in some stories the creators of Japan and all the gods and humans afterwards are descended from them. Izanagi was burned to death when she gave birth to the God of fire - proving that mortal/human gods can die. It would also explain how a "normal" human sorcerer has intimate knowledge of the the various workings and actions of the Shinto gods, the ability to wield a shinki - an ability otherwise restricted to gods - and the ability to body surf, similar to divine and demonic possession. It would also fit with the above idea that Yato is actually Tsyukiyomi - in how such a powerful deity could be captured, killed and then monopolized. It would also make him really and truly Yato's father.

Yukine will learn the god's greatest secret - who he was when he was alive and how he died - and will survive it.

• Perhaps evolving into something even more powerful, in the process by coming to terms with and accepting his death.
  • Half-confirmed, and half-jossed, all in the worst possible way. Father has Nora tempt Yukine into wanting to learn more, and suffers Sanity Slippage trying to as well as seeing Yato still trying to kill Father despite what it would mean for Yato. So he renounces his position as Hafuri Mono and becomes an Ayakashi, then is taken in by Father and given a new name, Hagusa, becoming a Shinki-Ayakashi hybrid. Father is now actively encouraging Hagusa to remember his past, and then kill any ties he has left to said past, so that he will have no one but Father left. And right now, he remembers all but the specific manner of his death, and is suffering so much mental deterioration that, while attacking Yato, he hallucinates that he's attacking his biological father.

Father is the child of a god and a human

• Despite being able to sustain Yato's existence by remembering him, Father is able to have shinki and is apparently able to posess other humans. He is also shown to be familiar with the inner workings of heaven, and is able to participate in judgements handed down by them. This is because he is half god and human. It would also explain how he seems to be able to live without a human remembering him - he remembers for himself.

Hiyori will end up like Tsuyu

• she will end up living a long and prosperous life and will even end up spreading the story of the god Yato through out her family and then some. Finally through her love and Devotion to Yato and Yukine she will love out the rest of her life as Spirit linked to a Sakura tree to honor the shinki that changed his life.

Father isn't a name or strictly a familial designation; it's a job title

• Namely, that of a Catholic priest. Father will turn out to be a Kakure Kirishitan persecuted by the Shogunate during or after the Shimabara Rebellion in the 1630's. Perhaps after seeing his friends or loved ones killed, he allowed himself to be consumed by his hatred/desire for revenge against the Shinto pantheon. He abandoned monotheism and created a god of calamity to serve as his unwitting tool for his vengeance — Yato. This will naturally play into the plot's climax.

A name given by the Koto no Ha influences the Shinki

• So far, we know of three Shinki named by the Koto no Ha instead of the normal way. Mizuchi, Edachi, and Hagusa.
  • Mizuchi is the name of a water serpent, and she can take the shape of, well, a water serpent.
  • Edachi can mean "Role, Service, Leader, War". He was also the Shinki to Bishamonten, a War God; he pretended to help her, effectively playing the role of a doctor, with the purpose of becoming Bishamon's guide post, thus the leader of her Shinki and in a way leading her, because he genuinely thought it was the best for her, thus providing the service a Shinki is supposed to provide. It also lead to the deaths of many other Shinki, which could also count as "War".
  • Hagusa, while literally meaning a certain type of weed resembling rice, can also mean "Bad One". Now that he has this name, he is hell-bent on revenge against his family, and tries to kill Yato, someone he before this was willing to die for.
    • As a bonus, one of the chapters in which he tries to kill Yato is titled "Echoes of the Koto no Ha".

Hiyori will become a God

It's firmly established that humans can become gods in this setting, as evident by Tenjin and Father, and that it doesn't matter how many followers they have, a God just needs to have followers, as Yato was born solely from Father, and Father's own shrine is cared for by a lone family.

So if a God can't be with a human, and becoming a Shinki could risk Hiyori losing her memory or becoming an Ayakashi, Hiyori will instead become a God herself somehow so she and Yato can be together. And considering her Cat Animal Motif, it will likely end up transmitting into her deity status.