Aria was the most annoying hate targeted character along the way, spanning past 350+ chapters

The MC puts a collar on Elga and essentially jumps into r*pe play without warning her, which makes her relive an old trauma (she was captured as a prisoner of war and almost r*ped as a young girl).

The MC actually r*pes Mirna. He takes advantage of a situation where they're trapped in a dungeon and she's hyperventilating because she's claustrophobic. Pretty sick actually.

Major spoilers:

Aira had the power to see truth, the past and the future all along (this was one of Solomon's four great spells that he created with pieces of his life). Despite this, she still makes many s*upid decisions and keeps the MC by her side knowing how often he's lied to her.

After the power sealed in Aira is removed, she can still use it for some reason. It's also never explained what it is about her that makes her capable of becoming such a powerful mage. (For the MC there's a specific reason.)

Aira holds a tournament to decide her husband and oscillates between treating the MC like tr*sh, saying she would have married anybody even if it wasn't the MC, then immediately after, becoming so needy she clings to him for four days. Really makes you hate everything about her.

At the tournament, the MC reveals the secret he's been desperately hiding to the whole audience for no reason. (For hundreds of chapters before this be insisted that Aira will kill him if she finds out he's the last Angmar, which is why he wants to have her fall in love first--except she clearly says before and after that she's not in love.)

The MC briefly travels into the past a few hours even though it directly contradicts everything else said about not being able to change the past. (What's more it consumes half his lifespan. It's not just this magic either, any strong magic consumes his life even though no other mage has that constraint. The author handwaves a reason for the life consumption, but I still find it extremely annoying when authors add in self harm as an artificial constraint to keep characters from behaving normally.)

King Solomon is "alive" in the past and apparently sending assassins to the future which is also not well explained. To be fair, it might be at the end of the novel, but given how much other stuff is poorly explained I'm not holding my breath.

After learning that both FL are basically walking lie detectors, our MC decides... to never feel any genuine affection towards any of them. Because that would be bad for him. His exact words. I seriously can't with this moron.

MC knows that first FL can only marry a high rank mage. So after accidentally becoming a mage and learning that he has massive growth potential, he does absolutely nothing about it for weeks. Mind you, he was b*tching about having no combat power before, multiple times.

s*x scene was bad.

Dozens of the early chapters are made to be a world-building part of the story, revealing part of MC pasts bit by bit, and his background stories with FLs. It doesn't feel boring, as it is made so that it got revealed very naturally along the progression of the story. Then MC got know of his past, and began to have an ambition to "tame" the FLs. I'm currently not so far along his "taming" process, so I can't comment much about it, but it's very enjoyable so far. The "taming" process is also happens naturally (idk if it's the right word for it) that even me that has read a lot of novels can't clearly tell who will get "tamed" by the MC in the future