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Just one, but it's a big one: what does everyone have against this guy? Everyone despises him right from the beginning, no exceptions. Why?
They don't really have anything against him personally. Everybody hates him because he's the Shield Hero. The Shield Hero has historically always been loved and worshipped as the personal hero of demi-humans, whom everybody in that specific kingdom hates with a burning passion. So since he's the Shield Hero, they want to do everything they can to ruin him... and in the process are turning him into the very hero of demi-humans they want to prevent.
Read the manga or the LN. There are some characters that hate him because they're projecting their hatred of demi-humans onto the figure of the Shield Hero. Others hate him because of the political reason mentioned above.
To add on to all the previous reasons mentioned, he was accused of raping the princess...in a matriarchy. That's probably the worst sin you could commit there. She lied, of course, but the King was predisposed to both believing his daughter AND hating the Shield Hero for his own reasons, so he effectively turned the whole kingdom against the guy.
What did Myne stand to gain by accusing Naofumi of raping her? Come to think of it, why did she accuse those other men before him of rape? Was she doing it For the Evulz?
Her main goal was to become Queen of Melromarc. Her mother, the current Queen, bypassed Malty in favor of her younger sister, Melty, due to Maltys awful personality. The Church of Three Heroes was planning on overthrowing Mirellia to seize the country, so she piggybacked on their plan to be their inside woman, so to speak. The first part was to remove the Shield Hero, Naofumi, and then steal the Cardinal Weapon replica. Of course, she never realized that the Church had no intention of letting her become Queen once shed outlived her usefulness. And yes, Naofumi points out that shes a moron for not realizing that herself in the manga and LN.
As for the other men she falsely lied about and got executed...shes a sadist who gets off on seeing others in pain and misery. So yeah, For the Evulz
She's the soul fragment of evil deity that's just as malicious, evil and sadistic as she is, if not more so. Myne accused him because she was born evil and derives pleasure from being evil, just like the evil goddess she came from. So it actually goes beyond For the Evulz and into Made of Evil territory. Myne is likely incapable of acting benevolently in any fashion.
It's said that you need all four heroes to stop the Waves, so what was the plan if the king or the church HAD killed the Shield Hero? The only way to summon another shield hero would be to kill all the other heroes and then you're back in the same spot.
Wait a minute, you mean to tell me that the Bow Hero brings down a corrupt government but he never even bothered to check up on them to see if they're alright? In fact, why did none of the other heroes (except Naofumi) ever check up on their good deeds?
They were thoughtless and selfish, not to mention that they are operating on video game logic — aka "everything resolves itself once the mission is over". To their credit, Ren and Itsuki do regret their failure after it's pointed out to them.
Naofumi's shield can change forms and powers. Won't that make it an overpowered weapon and yet it's looked down upon by humans?
Weirder still: if you use plain ol mmorpg logic, hes the ONLY tank, and (maybe) healer. Everyone else is DPS. They should be throwing themselves at his feet.
Remember that the Legendary Heroes only fight side by side during Waves. Otherwise being near each other negates any EXP gaining. They never have to party up for the majority of their time together, so they look to other party members for healers or tanks.
He has no real offensive ability (at first), so he has to rely on counter-attacks and more indirect methods, which make him seem useless in fights compared to everyone else.
Presumably, all the Legendary Weapons have the same abilities when it comes to leveling up. It's just that only Naofumi had taken the time and effort to actually study his shield and discover these abilities. The other heroes just rely on the base abilities of their respective weapons. Therefore, while they're higher leveled, they have a limited set of skills and low mastery of their weapons while Naofumi can fight off higher leveled foes simply by having a more diverse skillset and complete mastery of his shield.
I understand Naofumi not wanting to form a relationship with Raphtalia because she was still just a child when he found her. However from another point of view, she did biologically mature, or is it because of Raphatalia's lack of mental maturation?
Naofumi might easily adapt to the rules of the current world when called for, but he draws the limit when it comes to legal ages. Even if Raphalia looks like a young adult, her "mind" is nowhere near her physical age. Hence why he'd rather wait until she's legal in "his" mind, after she's matured due to passage of time and actual life experiences.
He could be oblivious due to lingering trust issues. Or he could be refusing to pursue any relationships due to said trust issues in addition to the above.
In the web novel, he really is that dense. Motoyasu even calls him out on it in Chapter 100.
He also knows that he'll go back to his own world eventually, and there's no apparent way to take anyone with him. He wouldn't want any hearts broken when that time comes.
There's also the fact that he, in part, raised her after buying her as a slave. He might have some lingering paternal feelings for Raphtalia, and that becomes too much Squick for him to consider a romantic relationship for his surrogate daughter.
He also still has an aversion to women and romance up until Atla's death so many times when being confronted with evidence of her love for him, he rationalizes it away as her not having time for love and other excuses.
In the anime, it is implied that the trauma caused by Myne's betrayal caused him to keep seeing her as her child self.
Nothing odd there. After all, "virgin" is also synonymous with "unmarried woman" in the eyes of a child or "untouched" by the eyes of religious beliefs. No wonder she believes what she believes about the misunderstanding mentioned above.
Why did the anime change Fitoria's threat to Naofumi? In episode 16, 17 and 18, Fitoria is criticizing Naofumi for not trying to make up with the other heroes. The anime plays it off like Naofumi, the victim of the situation, is the one solely at fault for the things that have happened to him. Yet this doesn't make sense as no one would bother to help Naofumi, never mind try to hear him out, and Fitoria should already know this as she knows that the Shield Hero is hated in Melromarc. For anyone who's read the LN or Manga, this interaction doesn't exist, instead it's just her demanding that Naofumi bury his grudges; unconcerned by what they were.
Of all the people they could've picked to wield the Spear, why did it have to be a gullible, stubbornly deluded, skirt-chasing imbecile like Motoyasu Kitamura, who believes women can't be wrong or evil and refuses to live outside his own little world!? Were they so desperate that they couldn't pick someone smarter or wiser!?
You're presuming that the summoners actually get to pick the candidates for the four weapons before summoning them. That said, the summoning ritual is practically a "gacha game" on a insane scale. You put the coin in and what you get is what you got.
Did I say "picked" and "pick?" I meant "gotten" and "get." Regardless even if this was the case couldn't the forces there invoked have exercised a some measure of scrutiny!? Surely those forces had the power to choose which dead people became which heroes, unless a certain "goddess" was deliberately meddling in affairs to her advantage. In which case I rescind my argument.
It's just another jab at the "Isekai"-genre in general. Considering how many of those protagonists have a tendency to be loners, losers, NEETs, otakus or people so bland and insignificant or plain insufferable that they need to enter a whole different universe just to stick out from the background, the selection process might go by the priority of "pick people that nobody will notice or miss in their original worlds". The poor selection of these four are just the testament on how poorly it would turn out to have these kind of people dragged into this kind of situation with four different heroes to further be deconstructed. The four types being The Anti-Hero (Naofumi), the Idiot Hero (Motoyasu), the Ideal Hero (Itsuki) and The Drifter (Ren) being deconstructed down to the core.
Did they ever explain WHY Glass and L'Arc had to kill heroes from another world to save their world or delay the Wave? How would killing delay the Wave in any way?
It's explained later in the Web/Light Novel (the anime & manga have not reached this point yet, so beware of spoilers). Details below: The Waves of Calamity are caused by two worlds colliding and bleeding into each other. The Waves become deadlier and destroy the world faster if one or more of its Heroes is killed. Once one world dies, the other world will be free of the Waves (at least for a while until another world starts colliding with it). One symptom of the Waves is the presence of demi-humans, who were not originally native to Melromarc. In the web novel, the Waves are instigated by Medea Pideth Machina who drains each world's energies and revels in the suffering.
Why didn't the Queen of Melromarc, upon learning how the Shield Hero was treated in her country, didn't just send him off to the other countries where he will be treated like the hero that he is? Given how she was working herself to the ground just to pacify the other countries when they learned that Melromarc summoned all 4 heroes and was working extra hard just to keep secret how the Shield Hero was being treated, it would've been easier to just take Naofumi and send him to the neighboring countries, especially those that will gladly choose to summon the Shield Hero and treat him with respect. Also Naofumi would gladly leave Melromarc given the chance because of how he was treated.
Pragmatically, it's because he's useful in battles (especially during the Waves) for his Stone Wall and supporting capabilities. And despite charging for his services, Naofumi has saved numerous lives, especially with his medicines.
Politically, having him on Melromarc's side acts as a deterrent against war, especially from countries like Shieldfreeden and Siltvelt who revere the Shield Hero and would be enraged by Naofumi's poor treatment.
If he was sent to one of the countries that worships the Shield Hero, they'd definitely learn how badly he was treated and it could have potentially have started a war.
The other countries are already pissed that Melromarc violated the agreement in how the Heroes were to be summoned. It is in her kingdom's best interest to mend relationships with the Shield Hero and help train all the Legendary Heroes to fight now in her care. Otherwise she'd send them off and lose what little leverage she has against already angry leaders.
How does Raphtalia still have a slave seal by the end of the first season? She was originally bought by Naofumi during his Then Let Me Be Evil period, and when he thought that a geas was the only way he could trust anyone in this world. After her seal was removed, Raphtalia surprisingly decided to have a new one put on her, perhaps because she believed that Naofumi still had to relearn to trust. But why keep it after all this time? Was it actually Raphtalia's way to swear a lifelong oath of fealty? Does she consider herself Property of Love? Or is the "slaver's shield" skill tree just too good to pass up, compared to regular party-member options?
There are a few reasons. Yes the slave owner's shield comes with a variety of bonuses that boosts the growth of the slaves contracted to him similar to the monster owner shield. This is why later when he builds his village he has everyone get a crest and even reset their levels so they can get the bonuses. Next, Naofumi still has trust issues and Raphtalia knowing this willingly enters into the contract again so he can fully trust her. Lastly, and this is only in the Web Novel, Raphtalia actually has more rights as Naofumi's slave in Melromarc than if she were on her own. Even discounting that, she essentially is a slave in name only after the duel with Motoyasu.