This is one of those anime that started off strong and successfully hooked me in the first episode – heck, the way it had me laughing, it hooked me in the first five minutes – but then just kind of… failed to keep me invested, ya know?
I’m Quitting Heroing is a shorter anime, only twelve episodes, and it begins just after the stereotypical final battle between the hero and the ruler of demons. The demon army is in shambles, but the hero, Leo, is so strong that he terrifies the humans he has protected. They exile him, so he goes and joins the demons. The demon queen, Echidna, refuses at first, because she hates how badly she lost to him. Hilarity and poignant thoughts follow as her generals hire the hero behind her back and make use of his services to repair their forces without her finding out, at least not until they can indisputably argue for how useful he is.
The first half or so of the show is actually quite amusing and endearing, as Leo gets to know each of the generals, and Echidna herself, helping each of them with their assigned tasks as best he can. He makes fun of the sorceress Shutina even while he manages to lighten her workload; he tries to teach the beast-girl Lily how to work better with others, and ends up learning that his methods were far too convoluted; he educates Edwald the dragon warrior in the amateurish mistake of assuming that everyone can do what you can do if they just work hard at it; he teaches the Melnes the assassin how to connect with people, and is one of the first that Melnes connects with; and he has dinner with Echidna, learning of her hopes and dreams and kindness in the process.
I particularly liked that part, showing how these demon generals were like real people, and not bad people, and the things they have to think about in order to run an entire army.
Leo also learns about each of them and opens up enough to tell them who he truly is. He is a bioweapon, meaning a living creature that was created by human scientists back during the Age of Machines, some three thousand years ago – which turns out to be our modern day – for the purpose of protecting humanity from the encroaching evil of the demons. He is the last of his kind, the other eleven bioweapons having all died in battle, and he has grown very strong… and very unstable.
The show, which was mostly lighthearted and fanciful, suddenly goes into a sudden climax with the sudden revelation that Leo the Hero is being driven insane by his ancient programming, that he is aware of what is happening to his mind, and that he needs to be killed before he, himself, destroys humanity and demonkind alike. That is why he wanted to join the demon army, to see if Echidna was worthy of the priceless treasure he must leave behind, and to get her and her generals to kill him.

“This plot is really a mess! Goes everywhere, way too fast!”
So, it starts out fun and goofy, then drags out a bit with the hero’s prolonged backstory and self-reflections, and then, with no warning whatsoever, it’s a dire, potentially apocalyptic, emergency with severely high personal stakes.
Now, nothing against that in and of itself, but it was a bit off-putting, and… well… to be honest we hadn’t spent nearly enough time with these characters or gotten to know and love them nearly so well in order for me to feel invested in the outcome of this surprise showdown.
Which got drawn out. It began in one episode, occurred in the next which ended in the use of a desperate final move, and then the episode after that took the entire episode for that one attack to actually happen while we waited through yet more reflections from both Leo and Echidna, and finally, at long last, they ended the showdown with a cheap cop-out to avoid the tragedy that they just spent three episodes building up to.
Is it terrible of me to have felt a little bit cheated by that?
First we’re goofy, then we’re suddenly tragic, then the problem just goes away. It was like feeling the storytelling version of whiplash.
So it started out pretty good, but then went all over the place, with very little structure to it. It slammed us with a tragic climax that ought to have rent our hearts, but did a poor job of it, and then let us down at the end just to get an ambiguous happily ever after without any price paid for it.
It’s not all bad, but it’s certainly not so great, either!
Rating: I give I’m Quitting Heroing 6 stars out of 10.
Grade: C-Minus.
…I did enjoy the character designs, though.