As the Demon King, I'm Just So Tired

The door was kicked open with a bang. “Demon King, you've slaughtered countless lives and brought endless calamity to this world. It's time to settle this!” With that, the hero drew his sword and charged at Ran. “Right! You've got that right.” Yet Ran, the Demon King, showed no fighting spirit at all. But when the hero drew close, Ran gave the cloak behind him a light flick, sending the hero flying. The cover will take a while. I couldn't stand the Q-version image not matching the title, so I thought I'd write something in my spare time. No inspiration, so I'll just write.