He does look super dead ... but depending on the angle the arrow went in he could have just lost an eye. Also, what are the chances he got the girl(frienemy) pregnant in their last soiree. It would make manga/manwha logic sense that he left his seed on the day that he died.
If he IS dead then that proves there are some stakes in this and that it's not all nameless characters. But if he doesn't die ... that's gonna be one hell of a story to tell the kids (assuming the story ends like in my head cannon where they setup a village on the border where men and women live together after they take down the current king and queen).
Also, Edgelord is not dead ... probably. Who else to be a thorn in the side of the MMC other than Mr. Jelly-Pants over there. I mean, He SHOULD be dead. What with taking an arrow to the back AND falling off a cliff. But he is SUPER going to live ... maybe.