korean
it is korean, it's just that murim manhwas are typically set in china
I doubted your answers cuz i found so many chinese figure of speech and those chinese characters on the houses of the places the mc went to ( if it's actually a korean manhwa then those shouldn't have any chinese characters written in it) so I searched this in baidu (it's like google but chinese) and it's actually a chinese manhwa, 学士再生 this is the title of it. The korean names and words are there because it was translated to korean then as you can see it is now translated in english.
a quick search online says that this was written by soo yu hyun, which is a korean name. just saying, before the korean language was invented koreans actually used chinese. you will find chinese symbols occasionally on older historical buildings if you go to korea. also, as i said before, the settings of murim novels (which i've found to be mostly korean manhwas) are usually set in china for some reason? i may be incorrect about that but thats a general observation. however, this is a korean manhwa, as it was written by a korean person.
Ohhh
Just like how Japanese have kanji letters, Korean have hanja letters. Those are basically Chinese characters, especially the ones that Taiwan are still using. The pronunciation might be a bit different in those three languages, but the core meaning of the words are basically the same.
This is a chinese manhua right? Why are their names and some other things are written in korean? The places they went to are all places that are in china. The cover page is written in chinese.