One great source could be Archive of Our Own (AO3). There are numerous fanfics about Chishiya x Arisu there. You can filter by rating, length, and genre to find the ones that suit your taste.
The development can also be based on personal growth. Horikita is often very focused on her own goals and can be a bit cold. Ayanokoji could be the one to help her see the importance of relationships. Maybe he shows her how a more empathetic approach can help in achieving their class's success. This would lead to Horikita opening up to him more, and Ayanokoji in turn would start to show more of his true self to her. Over time, a deeper relationship could form as they both grow as individuals within the context of the fanfic.
In the light novel, Ayanokoji is clearly the more intelligent one. He has a unique ability to analyze situations and people's motives deeply. Ryuen often falls into Ayanokoji's traps because he doesn't fully understand Ayanokoji's true nature. Ayanokoji can anticipate Ryuen's moves and counter them effectively, while Ryuen struggles to keep up with Ayanokoji's complex thinking.
They could be in a situation where they have to work together on a project for the school. Karuizawa Kei is initially hesitant because she doesn't trust Ayanokoji. However, as they face difficulties during the project, Ayanokoji's calm and intelligent approach starts to win her over. Their relationship then blossoms from there. For example, they might have to deal with a tight deadline and scarce resources, which forces them to rely on each other's strengths. This shared experience can be the foundation for their growing relationship.
I don't think it'll necessarily meet your needs, but I'll try my best to recommend a novel that's most relevant to your description."Being in Tokyo is the king of light novels." This book is a light novel written by the author, Ling Ling. It's a daily love novel.
Accidentally lost his soul to a loser from Japan. He had no money to live on and had to embark on the path of writing novels? Since he didn't know how to write light novels, he could just use cool novels to write. What childhood sweethearts? In front of my Dragon King son-in-law, the invincible War God, they are all weak! A beautiful girl from a novel? I'm sorry, I really have someone who wrote cool articles to capture me…
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"Traversing the Other World: Two Dimensional" was a light novel by the author, the Winged Knight. The general plot of this novel was:
[Total: Cultivation vs anime, transmigration vs transmigration, system vs system, fantasy vs 2D…]
As the main character, he wanted to roam the other world... and travel through the 2D world...
In the chaotic and noisy modern city, there was a strange monster that ate dead bodies. People called it the monster. He was the Grim Reaper, an angel on one side and a demon on the other. The two sides were swapped, and he wanted to play the role of Tokyo.
[The alternate world is paused. The world is currently in progress: Tokyo Ghoul]
The new book,"The Young Marshal from Dragon Ball" has been released. Please support me and watch it, hehe!
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I Raise Horse Racing in Tokyo was a novel about urban life written by the author, Ryo Yoshiaki. The general plot of the novel was:
He was reborn in Hokkaido and became a rancher. However, Koichi had never thought that he would be in so much debt because of a horse after graduating. Fortunately, this horse was called the Golden Ship. And his debut was the future grand prize, the Gold Master. From then on, Koichi became a professional jacker for all kinds of problematic horses. It set off a gust of wind in this boring world...
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"I'm a Ninja in Tokyo" was a light novel by the author, Fat Otaku. It was a derivative Doujinshi novel. The general plot of the novel was:
When Yuichi realized that the Naruto comic book in his hand had turned into a black hole and sucked him in, he was in despair... When Yuichi realized that he was still in modern society, he cheered and extended his sinful pig trotters to the galgame... When he was satisfied with a big bag of potato chips and coke, he saw..."You want me to fight with this... thing barehanded!" "Armory has been added to the system. Please check!" It could be considered as a comprehensive manga world view. The passerby female protagonist, Chun Wu, Onmyoji, Tokyo Dark Crow, Monogatari, Sly Ghost, Natsume, and other world views were combined. If you like it, you can take a look~~
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"The First Person of the Grand Pavilion of the Warring States Period" was a historical novel written by the author Despicable General. The general plot of this novel was:
There was Japan's strongest soldier, Sanada Shinkou. Two days, first-class two-sword-style Miyamoto Musashi. There are many loyal and victorious people in the east, and there are many beautiful and beautiful people in the west. There are three heroes of the Warring States Period, Oda Nobunaga, Toyotomi Hideyoshi, Tokugawa Ieyasu. Three tube four positions North Hatake, Sipo, Hosokawa, Ishiko, red pine, mountain name, Kyoto pole. There are four heavenly kings, four heavenly kings, five heavenly kings, five heavenly kings, The Eastern Sea Path, the Eastern Mountain Path, the Northern Land Path, the Shanyang Path, the Shanyin Path, the Southern Sea Path, and the Western Sea Path. There are sixty-six countries in the Warring States Period, seven of which are cheap mountains, seven guns, Kato Kiyoshi, Fukuyama Masanori, Zaoya Takeshi, Katakiri-kito, Kato Yoshiaki, Hirano Changtai, and Wakisaka Yasuharu.
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"Muye's White-Eyed Princess" was a light novel written by the author, Don't Be Reasonably Hack. The general plot of this novel was:
She had transmigrated to the wealthy Hinata clan in Kiba and became the young lady of Hatada. Hatata was determined not to be a good-for-nothing anymore. She had to enjoy the treatment that a rich lady deserved. Ban: Do you want to dance too? Hinata: I still want to dance! [PS: Daily joke title: My Shadow is the Strength of Ten Tails] Author: It's me! Please support me, big shots. I need all kinds of nutrition to grow new books.
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"Man Is the Grim Reaper in Tokyo" was a light novel written by the author, Dream Fairy Pig. It was a funny and sarcastic novel. The general plot of this novel was:
[New book has been released: Tokyo Wrist Hero] Reincarnated in Tokyo, where evil spirits were everywhere, the Zhong God Taiyi awakened the Zankita and inherited the Spirit Removal Firm.
From then on, she was the daughter of a sword hero, a demon fox drinking friend, a blind date demon, a chuunibyou spirit master, a social animal child-sending god, an eight-headed snake man, an Ichuan warrior spirit...
They flooded into his life.
"There's nothing in this world that can't be solved with a single sword strike.
"If there is.
"Then let's use Soaring Dragon Flash, Crescent Moon Sky Charge, Three Thousand Worlds... Let's solve it!"
[Invincible Style Daily Comedy].
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"Governor's Ambition" was a historical novel written by the author Dongfang Sheng. The general plot of the novel was:
What would happen if an ordinary person returned to the past? The correct answer was that he would die. Because I don't have a household register or a temporary residence permit, hahahahaha.
However, this is a novel and we are back in the Warring States Period of Japan, so it is different. Watching an ordinary person deal with the famous generals of the Warring States Period, Nobunaga Oda, Hideyoshi Toyotomi, Ieyasu Tokugawa, Nobuhiro Takeda, Kenshin Uesugi…How much would history change?
Book friend group: 49944105.
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"I'm in Tokyo, and I have a Wishing Machine" was a light novel written by Not Floating Cloud. It was a fantasy novel. The general plot of the novel was:
Her body was sunk into Tokyo Bay, and no one was looking after her child. The fat on her chest is too heavy. Do you want me to help reduce it? Woof woof! A dog actually wanted to avenge its master! With the wishing machine, he traveled to Tokyo, Japan, in a parallel universe. Higashino Hirosawa complained about all kinds of strange wish requests from time to time. However, for the sake of his grand goal of exploding with a single punch! Bring it on!
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"Daily Death from Blade Fangs" was a light novel, a derivative Doujinshi novel, written by the author, Xing Jiu. The general plot of this novel was:
In Blade Fangs World, Phomma Yujiro, who had the title of the strongest creature on the surface, praised him as the most "filial" and "delicious" son! In Su Qing's world, the Goddess of Water, Akuya, gritted her teeth and called him the worst knight who blasphemed the gods! In the God Slayer world, he was the king who usurped divine power and was known as the strongest demon king by the world! "Hello, my name is Fan Ma Qianxun." The beautiful youth said. Blade Fangs-Blessing to the Beautiful World-Slash! Crimson Pupil-Godslayer-Life in the Other World Starting from Zero-The Final Valkyrie-Was it Wrong to Encounter in the Underground City?
One plot idea could be that Ayanokoji and Horikita are paired up for a special project in the school. As they work together, Horikita starts to notice the hidden depths of Ayanokoji's character that she hadn't seen before. This makes her view him in a new light and their relationship begins to develop.