Its common phrase in Korean Manhwa .. like, MC is always being bullied or something
Not really. It's one thing to have a couple of characters with rude personalities, its another to make every single character including the waiter rude. Hospitality in Korea is at the very high end of the spectrum that they cant even reject a horrible customer, unless its a family business or something. (Its kinda sad yet you know you're gonna be treated with respect). I'm not trying to compare it to reality since its a work of fiction. It's just not very sensible to read cursing from every single character there. Its unbalanced. Variety of personalities in characters is entertaining to read. One trick ponies on everyone gets old.
Art's pretty, hard to like the characters though since everyone is a jackass and spouting plain insults as a hello instead of having an intellectual talk. Hopefully dialogue becomes better.