I have to agree with degenerateafro. I let it slide when we found out the way the MC formed contracts with the top tier spirits was to promise them a way to defeat their boredom. I moved on, "okay, whatever, cliche and weak, but whatever." What bothered me the most is MC was presented as an intelligent tactician, yet when we get to this arc MC never asked or thought to find out if there was any place in the world, or anything in this world that would be his natural weakness. Something against magic. He goes to learn about Daba from the Pig Traitor, I mean this dude is a traitor so why would you believe anything he has to say? Then finds out upon entering Daba that it has an anti-magic field? That did it for me. That was so forced by the author it was ridiculous. It made MC look stupid for letting the king, EVEN THE QUEEN, and Pig Traitor play him like that without so much as an attempt to find out further information on the kingdom you so arrogantly go to thinking all you'd have to do is yell "Presto Chango!" and you win.
Yes, I'm aware author may choose to pull some plot armor out of thin air. I've seen the posts about author's previous stories, this does not necessarily mean the author won't change up for this story and let MC magically, excuse the pun, fix the problem.
I also disagree with everyone wanting the sister to get raped. She's already learned her lesson, that much is obvious from the final few panels. That was obvious the moment the lizard guy thought to betray her. UNLESS author takes the approach of making her a stubborn optimist who believes their talk-no-jutsu or values when pushed on others will win everyone over like a typical shounen MC. Bad part is, she's not the typical shounen MC, she's the side character to the MC so her MC-superpower is null. Still, she's obviously learned her lesson and there's no need from a story perspective to go any further. People don't read and write stories to invoke every facet of the real world into them so bringing up "This is how the real world works" is moot for a fantasy story. The moment Sasae lost his arm it was apparent she learned her lesson. Your anger toward the character does not need to manipulate the story.
Still, I found myself wondering why these countries are fighting each other at all when they have a shared enemy? Why was their internal fighting in the country as well? That made no sense? Why would the country standing at the threshold against the world enemy not want to fortify their front line defense? That's so typical of some authors. Let's have political intrigue that wouldn't really make sense in a situation like this, but draaaaaammmaaa! I'm not saying there wouldn't be any opportunist, but the king is an idiot if he allows class warfare or whatever to overwhelm his duty to protect his land. Why has it survived this long and not been overrun if leadership is this incompetent?
MC is silly as well. He goes overboard to protect his mom/love interest, older sister/love interest, and younger sister/love interest. So far, he lets them each be fighters while he sells his soul to be the magician?
He doesn't just launch a meteor at Daba the moment they got out of line? What? Anti-magic field or not, before he knew of it, of course, he should've been able to stand on the outskirts and launch a meteor and the momentum smashes into the country. It would've taken them out or forced them to leave and face off against the kingdom's forces outside of their anti-magic protection. Yet, of course, how would he know to do this since he didn't get all the information on Daba. Which leads me back to my beef with this arc. He trusted the Pig Traitor, let the King dictate what needed to happen, and didn't even ask the Queen about where he was going? Yet, author wants us to believe MC is so clever?
If he manages to shoot magic through his severed arm because it was somehow taken with his sister then I'm done. That'd be too much dues ex machina, plot armor pull nonsense. It won't be clever. Just ridiculous. Cleverness would've been him going around and finding out how to destabilize the field or something, actually learning they had one before all this and maybe destroying the place or causing a war of attrition by using magic attacks just outside the field and cutting off trade or whatever with the Daba people. Something, anything that's not an out of thin air pull of silliness.
