The official website for the upcoming TV anime adaptation of Kōcha Agasawa’s popular manga series, The Ramparts of Ice (Koori no Jyōheki), has unveiled a new visual and teaser promotional video, confirming its main cast, key staff, and an April 2026 premiere date. The anime will air on TBS and other channels, bringing the beloved slice-of-life youth story to screens next spring.
Unveiling the Main Voice Cast
Leading the cast are four talented voice actors who will breathe life into the central characters of this high school drama. Anna Nagase is set to voice the protagonist, Koyuki Hikawa, a character often misperceived as intimidating due to her reserved nature and difficulty with social interactions. Joining her are Fuka Izumi as Miki Azumi, Koyuki’s childhood friend and a popular figure at school, and Shoya Chiba as Minato Amamiya, the persistent boy who aims to break through Koyuki’s emotional walls. Rounding out the main quartet is Satoshi Inomata as Yota Hino, a laid-back and considerate basketball player.
The Creative Minds Behind the Adaptation
Studio KAI, known for its work on various anime titles, will be handling the animation production for The Ramparts of Ice. The production team includes:
- Director: Mankyu (known for The Idolmaster: Shiny Colors and The Ice Guy and His Cool Female Colleague)
- Series Composer: Yasuhiro Nakanishi (Chained Soldier, Kaguya-sama: Love is War)
- Character Designer: Miki Ogino
- Music Composers: Kanade Sakuma and Natsumi Tabuchi
The original source material, Agasawa’s manga, is also credited for cooperation with the Margaret Editorial Department.
The Story of The Ramparts of Ice
The Ramparts of Ice (Koori no Jyōheki) tells a frustrating yet heartwarming story of youth, revolving around four intertwined high school students. At its core is Koyuki Hikawa, a high schooler who struggles with social interactions and, as a result, inadvertently builds an invisible wall between herself and others. Her only consistent companion is her childhood friend, Miki Azumi.
However, Koyuki’s solitary days begin to change with the arrival of Minato Amamiya, a boy who persistently attempts to close the distance between them. Alongside the amiable Yota Hino, these four navigate the complexities of high school life, forming unexpected friendships and exploring a web of emotions and unspoken feelings.
Manga’s Journey to Anime
Kōcha Agasawa’s The Ramparts of Ice originated as a self-published webtoon before being serialized on LINE Manga from January 2020 to April 2022. Shueisha later published the series in 14 tankōbon volumes under the Jump Comics label, with the final volume released in February 2025.
The manga has garnered significant recognition, including a special award at the 2nd Shueisha Shojo Manga Grand Prix and ranking first in Comic Natalie’s Tateyomi Manga Award 2024 in the Completed category. It also placed second in AnimeJapan’s “Most Wanted Anime Adaptation” poll in 2023, signaling strong fan demand for an anime adaptation. The anime adaptation was initially announced in January 2025.