|Height||155 cm (5'1")|
|Weight||43 kg (94 lbs)|
|Occupation||Founder of the Mekakushi Dan / Student|
Deceased / Inside of Heat Haze
|Manga||12. Yuukei Yesterday III|
|Anime||01. Jinzou Enemy|
|Novel||カゲロウデイズ II -a headphone actor-|
|“||What do you think is the reason for my death?||”|
Ayano Tateyama (楯山文乃 Tateyama Ayano) was a classmate and close friend of Shintaro Kisaragi and the original founder of the Mekakushi Dan. She committed suicide by jumping off of the roof of her school.
- Ayano is a girl with long brown hair, with two red clips attached to her left fringe. Her eyes are colored in a dark brown, though they sometimes appear grey. In Toumei Answer, she is seen wearing a red scarf and a black school uniform with a white ribbon attached to it. Her stockings are black and her shoes are dark brown. As she grew up her school uniform changed into a lighter colored one with a bow attached at the chest area.
- At the end of Mekakucity Actors, she is seen wearing a white dress, trimmed with a thin red bow above her chest. 
- The daughter of a teacher, Kenjirou and an archaeologist, Ayaka, as well as the founder and first leader of the Mekakushi Dan. Her member number at the time was "0".
- She was a cheerful girl who was Shintaro's classmate during middle and high school. Although always staying at Shintaro's side, she did not believe in her abilities to put him out of his apathy. It is presumed that she got rather low grades, as she was seen with only a 56 as a test score once. Even though she called herself stupid, she was always smiling and seemed to be having fun.
- Ayano cares deeply for her family and wants nothing more than for them to be happy, even if everyone couldn't be together. She treated her adopted siblings equally and always played with them when they were younger. Her sacrifice was the ultimate price she paid for her remaining family to be happy; even though she wanted to have her mother back, she refused to see anyone hurt or dead because of it.
- Favoring Eyes: (目をかける Me wo Kakeru) Her eye ability allows her to project her emotions onto others, which she refers to as "the power of caring".
- Her favorite character is Noriaki Kakyoin from JoJo's Bizarre Adventure.
- She tended to fold little paper cranes out of Shintaro's tests to cheer him up. Paper cranes stand for happiness and a long life, whether Ayano knew of this symbolism is unknown.
- She thinks the red jersey Shintaro wears suits him.
- It was confirmed by Jin that Ayano was Mekakushi Dan member No.0, as she was the original founder.
- In the Children Record Booklet it is stated that Ayano has black hair. However, she has never been shown with black, but instead always dark brown hair.
- She used to wear her hair clips in a cross shape when she was younger, then wore them parallel as she got older. The way her hair clips are placed may be to resemble her mother Ayaka.
- The hoodies she gave to Kano, Kido, and Seto when they were little were to help keep their eye powers from showing.
- Ayano is the first character to appear in the anime.
- "No, I'm no good for him. He needs someone that's even more selfish than him, someone energetic to pull him along... All I do is just follow behind him all the time. I can't do anything..." - (Ayano about Shintaro)
- "Ehehe. I’m stupid, you know. So it can't be helped." - Children Record Booklet
- "What do you think is the reason for my death?" - (To Shintaro in 18. Kagerou Daze I)
- "I hope everyone was introduced properly. Um, Mekakucity Actors is starting soon. We'll all do our best, so I'd be happy for your support. That was nervewracking...." - (Mekakucity Actors Commercial)