In terms of the style and vibes, the worldbuilding is more subdued like .hack//Sign rather than SAO or Murim Login. The world is immersive because the politics are introduced slowly instead of Sect drama dumped at once (it still dumps drama but not as badly as some comics).
Unfortunately, when the game RPG popups appear, they ruin the immersion, but I guess notification screens are part of the genre...zzz...
The overarching plot is rigid and artificial, because the MC is forced to complete his main quest just because the popups tell him to. However I like that the quests are exploratory and more than just "number go up." Also the MC is level-headed and strategic, and he is analytical compared to typical shonen protagonist. His reactions are believable which I appreciate. I look forward to how he adapts to his environment.
Some sources say that the studio behind Teenage Mercenary is also behind Teenage Swordsman. I definitely think both manhwas lean toward realism. The MC in Teenage Swordsman has advantages but isn't as OP as the MC in Teenage Mercenary (if Ijin walks in a room you can expect an ass-whooping, but if Harang walks in a room it doesn't change the predicament much).
In terms of character design, it's hit and miss. I like the fantasy cultures and their overall aesthetic, but the individual characters have inconsistent designs that don't make sense (like one girl wears a plain tank top while everyone else wears long-sleeved hanfu).
This story is a good middle-ground between brainless OP protagonist and underdog story. Characters are decent enough, conflicts have twists and plans go wrong.
