Why Was the Ascendance of a Bookworm Anime Opening Replaced? Comparing the AI-Generated Version and the Original
Ascendance of a Bookworm is a popular light novel and manga series, but its anime opening sparked controversy after generative AI was used in its production. As a result, the original opening was replaced.
So, which parts of the Ascendance of a Bookworm opening used generative AI, and why was it replaced?
In this article, we'll compare the original and replacement openings to show exactly where generative AI was used and what changed.
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Why Was the Ascendance of a Bookworm Anime Opening Replaced? Comparing the AI-Generated Version and the Original
Where can I find the AI that generated the opening theme for the *Ascendance of a Bookworm* anime?
It has been pointed out that generative AI was used for the “background art” in the opening sequence of *Ascendance of a Bookworm*.
Ha chances de que a nova temporada de Honzuki no Gekokujou, produzida no Wit, esteja usando I.A.
Nao e confirmado, mas alguns detalhes nos fundos da abertura sao bem suspeitos. Inconsistencia e incongruencia nos desenhos, borroes, baixa resolucao, sobreposicao de linhas etc. pic.twitter.com/gy0Il5FnUp
— Sakuga ONE 「作画1??」 (@sakugaone) April 4, 2026
- A wallpaper-style background featuring intricate, intricate patterns
- A soft background featuring flowers and plants
- A fantasy-themed background featuring stars, clouds, and the moon
It appears that materials generated by AI were used primarily for decorative backgrounds behind characters (e.g., walls with ornate patterns, floral backgrounds, and fantastical scenes like starry skies or the moon) during the background production process for “specific shots”—rather than for the entire opening sequence.
These details are hard to notice unless you pause the video and look closely, but detail-oriented fans overseas—particularly those sensitive to backgrounds and animation quality—suspected AI use due to the low quality, and the speculation seems to have spread.
【The OP in Question】
How the Use of Generative AI in the “Ascendance of a Bookworm” Opening Theme Was Discovered
The rumors that generative AI was used in the opening sequence of *Ascendance of a Bookworm* began shortly after the series premiered on Crunchyroll around April 4, 2026, when overseas X users began posting comments such as “The background looks like it was generated by AI” and “The quality is way too low.”
AI generated backgrounds in the opening of the new Ascendance of a Bookworm season. Very unfortunate. https://t.co/rbjknegFhr pic.twitter.com/V9CD6KIiMM
— ukloim (@ukloim) April 4, 2026
As word of this spread gradually within Japan, comments such as “But WIT Studio’s job postings explicitly prohibit the use of AI…” and “What’s going on with their production setup?” began to surface, bringing the issue to light.
Then, on April 10, 2026, WIT STUDIO officially acknowledged the use of generative AI on its official channels, and it appears the opening sequence was replaced following its cancellation.
Official Response Regarding the Generative AI-Created Opening Theme for the “Ascendance of a Bookworm” Anime
WIT STUDIO, the studio responsible for producing the opening sequence of the “Ascendance of a Bookworm” anime, officially acknowledged the use of generative AI on its official channel and took the following measures.
【Confirmed Facts】
During the production process for the background art in a specific shot from the opening sequence of Episode 1 of this series (hereinafter referred to as “the shot in question”), generative AI was used to create the source material.
【Future Measures】
① Redrawing
⇒ We will redraw the background art for the shot in question.
② Replacement of the Opening Sequence
⇒ Starting with Episode 2, we will replace the opening sequence with a final version that uses the revised background art.
【Other Information】
・As a general rule, we do not permit the use of generative AI in the video production of our works, including this series.
・This incident stems from deficiencies in our production management and quality control systems.
・To date, no use of generative AI has been confirmed in this series other than in this specific scene.
This official announcement has once again highlighted the fact that standards for the use of generative AI in the creative industry are currently enforced with extreme rigor.
WIT STUDIO’s clear statement that it “does not permit this as a general rule” underscores the studio’s firm stance of prioritizing the preservation of hand-drawn techniques and the protection of intellectual property rights.
Their swift response—deciding to immediately redraw and replace even background art, which is a minor detail—can be seen as a crucial measure to maintain the trust of fans and creators alike.
Was Ascendance of a Bookworm Canceled or Axed? Reasons Explained
Regarding the AI-generated opening sequence for the anime *Ascendance of a Bookworm*, as this issue touches on the very foundation of video production, many viewers—primarily on social media—are rushing to identify which shots were created using AI.
In Episode 1, viewers pointed out unnatural details and inconsistencies in the background art, and the officially acknowledged scenes became the main focus.
Comparing the original and revised versions shows that the AI-like textures were replaced with more natural hand-drawn artwork, highlighting the skill of the animators.
This incident also showed how difficult it is to balance traditional animation with new AI technology, and many people are watching to see how the industry will handle similar issues in the future.
⇒Watch the anime “Ascendance of a Bookworm” on Amazon Prime Video
