Otonashi Ayana

"Creation. Harmony... and Destruction. Their natures are completely different, but they're the same."

- Otonashi Ayana, It's my Own Invention

Otonashi Ayana (音無 彩名) is a mysterious girl who appears to all five of the protagonists at some point. She often appears at critical points in their lives to give them cryptic advice through riddles. She is a girl who sees everything, knows everything, but does nothing.

Appearance
Ayana has short, choppy pink hair, and mysterious violet eyes that seem to see all. She has a rather small and petite figure.

She's always seen wearing the girls' Kita High uniform with white thigh-high socks.

Takuji imagines her to be a futanari in one of his delusions, but this turns out to not be the case in reality.

Personality
Ayana is a mysterious, wise girl who seems to know the answer to every mystery. She has the presence of an otherworldly existence which scares people like Mamiya Takuji deeply. She always has a relaxed and stoic demeanor.

She's enigmatic and has a strange sense of humor, which the other characters don't understand and find unsettling. She loves making literary references and using them to give the protagonists hints to the truth through riddles.

She's a loner who spends most of her time hanging around the school rooftop, the only person she's been seen to consider a friend being Minakami Yuki. Due to Ayana spending nearly all her time on the roof, we don't see her interact with any character outside the five protagonists, and Iwata Miu in End Sky II.

Plot
Ayana is a being that seemingly exists outside the plot. She doesn't interact with or influence any of the events directly, but she often shows up to give the protagonists clues, hints and help that lead them in a certain direction.

Like when she lead both Yuki and Mamiya Hasaki up to the rooftop on July 20th in Down the Rabbit Hole II and Which Dreamed It respectively. Leading Yuki to the rooftop enables her final conversation with Takuji, and leading Hasaki to the rooftop allows her to grab on to Tomosane's falling body and save him.

Ayana also appears to Takashima Zakuro multiple times during Looking-glass Insects to speak with her. In the Kimika End of Looking-glass Insects, Ayana tells Zakuro that she has made the right choice, but still offers her the choice to sacrifice her wonderful everyday to see the souls take a different direction.

She's clearly aware of the conflict inside Tomosane, and speaks to the personalities that are unaware, like Takuji and Yuki about this in riddles.

In the End Sky II ending in Jabberwocky II, Yuki wakes up on the rooftop next to Ayana in a mysterious situation, with Tomosane's fate being left unknown. When she wakes up, it's almost like the incident never happened. The school is perfectly peaceful despite it having been the site of a cult group suicide just a day before.

Here, Ayana offers Yuki seven hypothesis on the truth behind this world, the seventh hypothesis being that "everyone in the world is me", and she tells Yuki to pick whichever hypothesis she likes the most. After her conversation with Yuki, she's called to graduation by Miu, and heads to the 'point where it all begins' once again.

Minakami Yuki
Ayana and Yuki often end up having conversations with each other due to both of them having tendencies to hang out at the school rooftop, and Ayana seems to consider Yuki a friend, though Yuki realizes Ayana is more than she lets on.

Mamiya Takuji
Takuji is intimidated by Ayana's presence, finding her creepy and disturbing, as a result, he displays hostility towards her in an attempt to drive his fear of her away as an existence he can't understand.

Takashima Zakuro
Ayana remains a mysterious, all knowing figure to Zakuro. Appearing during both endings of Insects to tell her whether her choice was right or wrong.

Mamiya Hasaki
Ayana appears to Hasaki at the end of Which Dreamed It and leads Hasaki up to the "End Sky", to the Building A rooftop Takuji is about to jump from, which allows Hasaki to grab on to him and stop him from falling.

Yuuki Tomosane
Ayana talks to Tomosane once while Takuji is trapped in a delusion, and Tomosane tells her of the dream Yuki told him of in Sawaimura, of being unable to stop a baby from crying and being filled with the overwhelming urge to end its life. Ayana later tells Takuji of this dream Tomosane told her of.

Trivia

 * Ayana is likely an author insert.
 * Ayana has only been seen to interact with Iwata Miu with the exception of the five protagonists.