Mark had no idea what being the unhinged king meant and he did not bother to find out about it either. For one thing, he was confident that it was a bug in his system since no one had titles. And for another, his behavior, as he knew quite well, had no relation to being unhinged.
Unless the system was trying to tell him he was the king of the mentally unstable, then it was definitely a bug.
Being an awakened didn't mean he was a match to monsters, even if they were weaker than his class. He had given in to his fate, so he was waiting for the monster to rip him to pieces.
But it never happened since he was saved just in time.
The agency arrived with a group of awakeneds, charged for the monster and killed it.