NezuKanaAo

NezuKanaAo is the Poly ship between Nezuko Kamado, Kanao Tsuyuri and Aoi Kanzaki from the Demon Slayer fandom.

Canon
The three haven't had any moments altogether but each of these KnY females have individually interacted with each other and have a good relationship with one another.

Nezuko and Kanao
Nezuko met Kanao at the Natagumo Mountain but their first encounter wasn’t pleasant as Kanao attempted to slay Nezuko due to her orders. Kanao was confused as to why Nezuko wasn’t attacking her. After a Kasugai Crow tells the slayers that Nezuko and Tanjiro are to be taken into custody. She bends down and asks her “Are you, Nezuko?”

Nezuko becomes able to speak after the Swordsmith Village Arc and stays at the Butterfly Mansion. Where Kanao is also staying. The Demon Slayer also shows Nezuko a butterfly on her hand.

After her battle with Douma, Kanao remembers a moment where Nezuko was clinging onto her skirt. Kanao says that she values her comrades with Nezuko being one of them.

Nezuko also remembered a time where Kanao smiled at Nezuko after she went inside of her box while she was turned into a human. So Nezuko has remembered times of the two interacting before.

Kanao and Aoi
Kanao and Aoi are both very close friends and have a sisterly bond with one another. Both of them have developed a very close bond while they were living at the Butterfly Mansion.

Back in their childhood while the two were at the Butterfly Mansion. Shinobu and Kanae placed down a bunch of random cards, containing names for the two that were suggested by them by other candidates Aoi actually holds a slight part on why Kanao has her name. As when Kanao was about to pick a name that said "Kamasu" Aoi immediately swapped it out with a card that said Kanao, so that she’d pick that instead.

However Aoi wasn’t as fortunate when it came to Kanao’s last name. Aoi really really really wanted a sister so she was desperately pestering Kanao to pick her last name “Kanzaki” but Kanao had made a decision that her last name would be "Tsuyuri" because it sounded prettier.

When Aoi and Naho were about to be kidnapped by the Sound Hashira. Kanao was going to flip her coin to decide what she should do. But after remembering what Tanjiro said about following your heart. As the Sound Hashira is about to leave Kanao clings onto the two and to stop him from leaving. Thanks to Tanjiro showing up and offering to go in Aoi’s place Tengen decides to release her and take Inosuke, Tanjiro and Zenitsu to go on his mission.

Aoi thanks Kanao and the others for stopping him after they return from the Entertainment District.

At one point Aoi thought it was difficult to deal with Kanao as she never felt emotions. Also since Kanao was capable of fighting Demons, Aoi felt inferior to her in a way. But their bond solely developed after Kanao had finally started expressing her emotions towards others and started making decisions independently.

Aoi and Nezuko
Aoi and Nezuko have not interacted much on screen. The relationship between them is unknown. But it is safe to presume that two have a friendly bond with each other to say the least.

Once Zenitsu claimed that Aoi was pretty scary. Tanjiro rebuttaled and said that she is a nice person at times. Tanjiro retaliates the moment where Aoi kindly polished and repaired Nezuko’s box after it was damaged by Sanemi Shinazugawa. Tanjiro obviously thanks her for the courtesy but she responds by saying “it’s her job after all”.

It is also likely that Aoi and Nezuko interacted during Nezuko’s stay at the Butterfly Mansion. Aoi also barged in when Zenitsu stole Shinobu’s pet goldfish to show it to Nezuko. Who thought it looked really nice. Even though Aoi was angry she didn’t punish Nezuko as she was aware that Nezuko likely didn’t know that Zenitsu took the goldfish from Shinobu’s room.

Fanon
NezuKanaAo is not fairly recognized by the fandom. Most people prefer to ship them as friends. Little people ship the three together in a romantic sense. There's little fanart of the three together. This ship is likely rare to come around because the three are all canonically married with Tanjiro (TanKana) Zenitsu (ZenNezu) and Inosuke (AoIno). But despite their canonical pairings this ship can be shipped alongside InoZenTan. Since in this situation the female trio doesn't end up with the male trio so they end up dating each other. Unfortunately it only has 4 works on Ao3. While the ship is not popular it overall it does contain two fairly popular Femslash ships. Those being NezuKana and KanaAoi.

Variations

 * NezuKana refers to the ship between Nezuko and Kanao
 * KanaAoi refers to the ship between Kanao and Aoi
 * AoiNezu refers to the ship between Aoi and Nezuko