I watched the anime for this a long time ago. I recently went back and read the light novels. To be honest, I liked the style of the anime more, though there were some issues with trying to fit too much into too few episodes. However, the anime only adapted a small part of the entire story. In my mind, the novels essentially have three major arcs. These involve a lighthearted build up that eventually leads to the main plot that comes to a climax, at which point it falls into a lighthearted build up for the next arc.
The first arc, which is the only part that the anime adapts, is mostly an introduction arc. It provides background on the world and introduces most of the major characters. The plot revolves around Akuto, an orphan who wishes to help society, being deemed as destined to become the demon king, and the the various adventures and trials he has as a result of this. This starts off lightly with a number of small stories that introduces him and the reader to a number of characters: Keena, another orphan that he met long ago; Junko, the daughter of essentially the head of defense of the nation; Korone, a Liladan, meaning essentially an artificial life form, sent to watch over him by the government; Fujiko, a black magician that wants him to embrace his inner Demon King and take over the world; Hiroshi, someone that seems destined to be a hero, but lacks confidence that he will be. It also introduces a world far into the future where magic exists granted by gods, where the magic itself is advances use of nanotechnology, and the gods are super advances AI. This premise actually leads of a bunch of inconsistencies, as can be expected from something that sounds pretty convoluted, but for the purposes of the first two arcs this isn’t a major issue. It also introduces the main villain organization, CIMO 8, who’s members are slowly introduces throughout all three arcs. During the first arc Akuto originally tries to get away from being a Demon King, but ultimately has to embrace it to protect someone close to him. In doing so, he makes an enemy out of the world, discovers that the world is far more complex than he originally thought, ends up killing a god, but ultimately things go back to normal due to Keena’s powers as the ‘Law of Identity’.
The second arc begins with another more lighthearted opening where they encounter a copy of Keena, who eventually disappears, but inadvertently also reveals a means creating and controlling virtual alternate dimensions. This is originally done by a member of CIMO 8 named V2 with help of Yoshihiko, an extremely intelligent and somewhat geeky but very cheerful girl. However, V2 attempts to use this to kill the demon king, upon which Yoshihiko turns the alternative virtual dimension into essentially an MMORPG that the Demon King and friends get trapped in. Yoshihiko at this point becomes one of the main characters, and assists the other main characters. They manage to escape, but in doing so release the original Demon King named ZERO, who V2 uses to take over the world. This further leads Akuto going on a journey to discover the roots of what it means to be a demon king and his origins, a meeting with the true empress, a major power up, betrayals, but ultimately a victory and things mostly going back to normal. Personally, I enjoyed this arc the most. It seemed the best blend of being serious and having depth, but at the same time feeling true to what the characters should be and creating a world that felt interesting and complex but also consistent. I would have loved it if it became adapted to an anime, though I doubt that that’ll happen at this point.
The third arc was where it jumped the shark. The plot originally begins with a fight over who would become the next ruler of the Empire. This leads to a war between a nation that had split off from the Empire, the Republic, as they also stated they held a claim on the throne, though the disagreement only escalated to war due to interference by members of CIMO 8. This also leads to a number of interesting situations and points. I especially found interesting how it was conveyed that a Demon King who had been ridiculed and hated from within the empire for no particular so far in the plot could suddenly became beloved when he was on their side versus an outside threat. However, the plot eventually got incredibly convoluted, with the characters themselves discovering that they are part of a story and that Akuto had the power to control everything in it. Akuto remakes the world an infinite number of times with the same characters having different backgrounds and personalities in each. I found this part especially annoying, because as a reader, I don’t want to be reminded that this is all just a story and that the author is free to meld anything to their will, and that all the characters are ultimately fake. For me enjoying stories such as these relies heavily on a suspension of disbelief and immersion into the story as if it is real, which is very difficult to do when the author tries to hammer into you that it is not. All the world building and characterization that had happened up to that point felt to be for naught. Furthermore, the plot got incredibly complex and used overly extravagant plot elements arbitrarily and gave explanations that calling convoluted would be an understatement. The ending itself was reasonably satisfying due to a reasonably good use of minimal story telling, but the path to it was ridiculous, and ultimately while I can’t say I hated it I can’t say I liked it either. Don’t get me wrong, this arc, even at its craziest points, also had a lot of good moments, especially in terms of the relationships between characters finally reaching their climax (*wink wink*), but overall the attempt at trying to make the story transcendent was more than I was expecting and I felt it didn’t really fit into the rest of the plot and ultimately hurt the entirety of the work.
In spite of the last arc not being to my tastes, I still liked the series overall . I liked most of the characters, and a few in particular. Akuto was amazing in that he tried that he had hopes and dreams that involved him not using his power, but was willing to abandon them and use his power when it became necessary without hesitation. He also held very strong views about the world around him, but was willing to change them as he gained experience and knowledge and ultimately he progressed a great deal over the course of the series. Hiroshi lacked the confidence to ever become a hero, but eventually became one in a sense, but then had conflicts over the use of borrowed power, but eventually came to a solid conclusion about what being a hero truly meant. Fujiko was incredibly sly and devilish, but was still kind when it matters, and incredibly dedicated. Yoshie had a very fun personality but also managed to very capable. The cast of characters was colorful and incredibly fun, though that somewhat makes the ending even more annoying. The world itself also got convoluted later on, but the world system that existed was very interesting and fleshed out, and the parallels to the real world and how they were explored was done pretty well most of the time, though that too also makes the ending somewhat more annoying.
So overall a pretty good series, despite the train-wreck at the end.