The Great Jahy Will Not Be Defeated!

The Great Jahy Will Not Be Defeated!

The Great Jahy Will Not Be Defeated anime series cover art
The Great Jahy Will Not Be Defeated

Series Overview

The Great Jahy Will Not Be Defeated! (Jahy-sama wa Kujikenai! / ジャヒー様はくじけない!) is a comedy series about a demon girl named Jahy attempting to restore the Dark Realm after it was destroyed by a magical girl. And since it takes place in our world, it’s technically a reverse isekai.

At the beginning of the series, a magical girl infiltrates the Dark Realm and destroys the source of its power, the mana crystal. This causes the Dark Realm to implode and send its non-mob inhabitants and the millions of shards of the mana crystal into our world.

Jahy, the former second in command of the Dark Realm only behind the Dark Lord, finds herself in this unfamiliar world. And without the power of the mana crystal, Jahy has regressed from her typically regal appearance to a chibi state.

The rest of the series follows Jahy as she battles the magical girl and collects shards of the mana crystal to both restore the Dark Realm and her own power. Or, at least, that’s what Jahy probably believed the rest of the series is going to be like at the start of her ordeal.

In reality, Jahy often gets distracted from her ultimate goal. She gets a job at a pub, becomes friends with a local elementary schooler, and spends more time thinking of plans to gather mana crystal shards than she does actually gathering them.

While not a slice of life anime, this series really is just about the daily life of Jahy and the various situations she gets herself in. And, as I’ll discuss in more detail later on in this review, that’s the glaring problem with The Great Jahy Will Not Be Defeated!

Main Characters

Jahy is the titular protagonist and former #2 of the Dark Realm. The majority of her personality at the start of the series revolves around her former standing in Dark Realm society. However, as the series progresses, she’s influenced more by humans and develops into a slightly less one-dimensional character.

Druj is a demon who served under Jahy within the Dark Realm and is completely committed to serving her in our world as well. But, unlike Jahy, Druj is extremely competent and succeeds at everything she does. This often leads Jahy to feel like a failure by comparison — which she is.

Kyouko Jinguu is the magical girl who destroyed the mana crystal and the entirety of the dark realm. When she’s not attending high school, she’s collecting shards of the mana crystal to prevent them from getting into the wrong hands and causing misfortune. However, she also seems to enjoy the misfortune these shards bring upon her.

Jahy from the anime series The Great Jahy Will Not Be Defeated

Store Manager is the manager of the pub Jahy is employed at. I actually didn’t realize that she didn’t have a name until I began writing this review. She’s the wholesome “ara ara ” type of character, which makes her one of the best characters in the series.

Landlady, who I’m also just now learning doesn’t have a name, is the younger sister of Store Manager and is Jahy’s landlord. The only reason she gave Jahy an apartment is because her older sister talked her into it — something she regrets every time she has to track Jahy down to collect rent.

And the last character I want to mention is Kokoro because she’s probably the best character in the whole series. Kokoro is an elementary schooler whom Jahy befriends while searching for mana crystal shards on a local playground. She reminds me a lot of Shiori from Non Non Biyori Nonstop.

Long, Slow, and Boring

Earlier in this review, I mentioned that the worst thing about the series is that it simply follows the daily life of Jahy. That may work fine in manga format. But when adapted into an anime, it ends up being painfully boring.

Most slice of life anime have something that makes them interesting. Usually, it’s the characters, but other times it’s the situations the characters find themselves in. The Great Jahy Will Not Be Defeated! doesn’t have good characters or many entertaining situations for those characters to interact within.

The aforementioned Non Non Biyori is infinitely more entertaining than Jahy, despite literally being about girls doing nothing in the middle of nowhere. Jahy has so much more to work with considering supernatural abilities are a part of the series. And yet, it somehow manages to do less.

Su from the anime series The Great Jahy Will Not Be Defeated

On top of being boring, the episodes all feel extremely slow. Since nothing entertaining happens for 22 minutes, it’s not much different from doing nothing for that time. Most of the time, I did something else, such as play a game, while watching the episodes. But when I didn’t, they felt like they were an hour long.

And, to make matters worse, this isn’t a single cour (12-episode) series, either. It has 20 episodes for you to slog through. I think making this a 20-episode anime is probably what made this series as bad as it is.

Think about it, if the series was condensed down to 12 episodes, each episode would have faster pacing and more would get accomplished in each one. Because the director had 20 episodes to work with, they spread all that content out even though it would have worked fine within a single cour.

Some episodes probably could have even been cut entirely, if I’m being honest.


The Great Jahy Will Not Be Defeated! is a 4/10 from me. It’s definitely a bad anime and I really wouldn’t recommend it. But it’s not as if it’s absolutely terrible. And I do think it probably works fine as a manga. The concept itself isn’t flawed, unlike plenty of other anime I’ve reviewed.

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