With absurdly long titles and distinctive settings, light novels have an endearing charm that captivates many. Still, avid readers often look towards the anime renditions of their favorite light novels, hoping to see their beloved characters in colorful frames and dynamic settings. However, these anticipations aren’t always met. After all, adaptations are prone to significant deviations.
Be it length constraints or censorship laws, anime adaptations are bound to undergo considerable changes from the source material. Since most anime adaptations of light novels serve as a source of marketing to draw in new readers, these series often conclude much earlier than the novels, forcing production studios to produce a satisfying conclusion of their own. This results in anime adaptations that have a considerably altered ending, differing almost entirely from the light novel’s conclusion.
5 Reborn to Master the Blade: From Hero-King to Extraordinary Squire
Reborn to Master the Blade: From Hero-King to Extraordinary Squire is based on a fantasy light novel set in a Kingdom ridden with dark gods and other enemies of humanity. Reincarnated as a woman, Hero-King Iglis begins his (now her) journey of mastering the art of the blade, all while exploring life as the opposite gender. The anime adaptation stays faithful to the light novels for the most part, with the ending being the only major deviation.
Since the 12-episode anime rendition became a standalone series, the ending is more conclusive and resolves most loose ends. The light novels, on the other hand, leave things more open-ended. This implies that more adventures are to come for Inglis, paving the way for future media. This holds true as the story continues on in the light novels from where the anime adaptation ends, marking differing conclusions for both mediums.
4 If It’s For My Daughter, I’d Even Defeat a Demon Lord
Fans of If It’s For My Daughter, I’d Even Defeat a Demon Lord had a hard time stomaching the light novel's daring conclusion. Most prefer the anime adaptation’s incomplete yet wholesome ending. The story revolves around the life of Dale, a young adventurer, and Latina, a demon child whom Dale finds deep within the forest. Despite belonging to different races, Dale ends up adopting Latina and raising her as his own daughter.
The rest of the anime follows a slice-of-life narrative with a few instances of adventure and magic. The anime concludes with the same theme, as the two navigate through their new father-daughter dynamic. However, the light novels take a more controversial approach, concluding the story with Dale and Latina’s marriage. The move put off many fans of the light novels. While the relationship may be more nuanced and complicated than it may initially appear, the notion of a father-daughter dynamic turning romantic didn't sit right with most readers.
3 Magical Revolution of the Reincarnated Princess and the Genius Young Lady
The title of Magical Revolution of the Reincarnated Princess and the Genius Young Lady may seem absurd. However, the story delves into some nuanced details, even incorporating a few shoujo-ai (lesbian romance) themes. The anime adaptation, though, eventually strays from the light novels with a rushed and convoluted ending that most fans did not appreciate.
The anime concludes with Euphie completing the Spirit Covenant contract, losing her humanity to become an immortal being. The light novels continue with the story, introducing a new antagonist who later becomes the cause of Anisphia’s newfound immortality.
2 I’m the Villainess, So I’m Taming the Final Boss
As an otome isekai series, I’m the Villainess, So I’m Taming the Final Boss adds a distinctive element to the isekai genre. The adaptation remains loyal to the light novels during the initial episodes. However, deviations in pacing and storytelling become apparent as the show progresses. Due to high chances of the adaptation becoming a standalone series, the production studio was forced to come up with a new conclusion, one that would stay true to the light novels while giving viewers a satisfying ending
However, the end result was far from ideal, and most fans didn't like the differences between the versions. In addition to the deviations in the ending, the adaptation misses out on several important events between Claude and Aileen, making the anime adaptation less preferable.
1 The Familiar Of Zero
The Familiar of Zero features an isekai premise. An ordinary boy from Japan is accidentally summoned by an inexperienced magic user in an alternate world. The anime adaptation initially remains faithful to the light novels, presenting the events of the original source material earnestly. Despite having multiple seasons, the anime begins to differ from the light novels and incorporates several creative elements of its own.
This could be attributed to each season supposedly being the last, but the show continuing despite rumors of its ending. This forced the studio to reopen plot lines after each concluded story, making a convoluted mess of the light novels. Eventually, the anime series concludes midway from the light novels, featuring a different ending where Saito and Luise visit Earth to meet Saito’s parents.