When Hajime and company find out that Myu, the little mermaid girl, had been kidnapped by slavers, their response is to completely wipe the organization out and free everyone. No mercy is had for any of the perpetrators, and the lead slaver isn't even spared a Pre-Mortem One-Liner before being triple-tapped in the head by Hajime himself.
In Volume 6 and the penultimate episode of the anime's second season, Hajime finally pays Daisuke Hiyama back for everything he did to him. In both cases, Hajime defeats his traitorous former tormentor effortlessly, before letting the villain experience what he had originally put Hajime through for himself. To mix in a bit of Nightmare Fuel, in the Light Novel, Hajime also subjected Hiyama to a savage beating before killing him.
Best Known for the Fanservice: The infamous Ass Shove scene with Hajime & Tio went viral on Youtube, garnering over a million views in a little over a month. It doesn't help that the scene in its entirety takes up almost a third of a whole episode.
Catharsis Factor: There is a massive satisfaction to seeing Hajime and his team rescuing the Hero's Party. Especially with the latter group's complete disbelief that the "stranger" that completely eclipses them them all in power is the same boy that most of them bullied back on Earth.
And later he also calls out Kouki on his soft-idealism, hubris, hypocrisy, and complete lack of resolve to truly get anything done.
Complete Monster: Ehitorujue is the god who rules Tortus. Slowly growing bored and lonely due to his immortal life, Ehito develops a cruel and sadistic personality after seeing his people suffering. To that end, Ehito manipulated several races to fight brutal wars and has his worshippers commit countless atrocities. Attempting to manifest himself in Tortus, Ehito attempts to bodyjack a powerful Vampire Princess, Yue. When that failed, he then set his sights towards a highschool student who has a misguided sense of justice which resulted on him and his classmates being summoned into another world. After Yue was released from her seal, Ehit successfully possessed Yue while torturing her inside out. After being expelled from Yue's body, he absorbs all of his creations in order to finish the heroes once and for all. It was soon revealed that Ehit's master plan was to destroy Tortus and attempts to find a new sandbox to play with in other worlds solely to satiate his boredom starting with Earth.
Hilarious in Hindsight: Tia Ballard playing Yue in the English dub. Yue is a Really 700 Years Old vampire who can cast powerful magic. In another of Ballard's recent roles, she played Entoma in Overlord, who notedly fought that show's resident magic casting vampire. And this won't be the last time she falls in love with a character voiced by Matt Shipman.
Jerkass Woobie: Eri might have been a disturbed Yandere, but after being raped by her stepdad and being beaten by her own mother, to the point she tried to kill herself, it's hard to not feel sorry for her.
Moral Event Horizon: Daisuke Hiyama was certainly despicable and unlikeable bully, but he really sinks low with his attempt on Hajime's life just so he can have Shirasaki all to himself. If that wasn't bad enough to cross it, then he definitely proved himself to be irredeemably evil when he conspired with Nakamura Eri to betray his classmates and the kingdom to demons just so he can kill Shirasaki and have her reanimated as a doll to love only him. Unlike his murder attempt with Hajime, the entire class does find out about his treachery and rightfully lose all patience with him, and Hajime (who didn't bother killing Daisuke because he deemed him not worth the effort) finally loses all sense of mercy towards him the moment Daisuke stabs Shirasaki, outright killing him by leaving him to be devoured by monsters, mirroring Daisuke's murder attempt and what Hajime had to go through in the abyss.
Hajime's use of his makeshift guns can be seen as this. In Japan, gun control laws are very strict, and only the police and the JSDF are authorized to use them. It's very, very difficult for a law-abiding citizen to own a firearm,note The only firearms legally available to non-law enforcement or JSDF personnel are shotguns, and after demonstrating a 10-year history of responsibly owning that, then rifles become available. In addition, both shotguns and rifles must "look" like hunting guns (essentially they must have wooden stocks and no pistol grips). Private ownership of handguns is completely illegal. and a very big taboo to even hold one (especially if the one holding it is still a minor since Children Are Innocent is at play in Japanese society). This serves as a metaphor on how badly Hajime's mental state has deteriorated in the Great Orcus Labyrinth.
Kouki's self-righteous Good Feels Good beliefs of justice, his view of bullying, and use of Victim-Blaming aren't all that different from how Japanese society views and deals with bullying along with being less individual-based (i.e. conforming to the group ideology, and if someone stands out in any way or disrupts the status quo, from something as simple as having low or high grades, or disagreeing with the group, to having a disability, they are ostracized for not meeting society's standards). In fact, Kouki's character can be seen as an allegory along with how the ugly sides of Japanese culture clashing in a European medieval fantasy-like setting, and the results aren't pretty, and come back to bite him in the ass and balls on more than several occasions.
, garnering over a million views in a little over a month. It doesn't help that the scene in its entirety takes up almost a third of a whole episode.