The Demon Lord's princess
In this world I can choose to; conquer and destroy, do bad deeds, kill like just eating on my daily life, etc, etc...
Instead of doing all those boring tasks, I chose to guard this princess as she was cursed then kill all princes. I'll be content living with her forever. Oh by the way, I'm the Demon Lord. Hell to meet you!
cover by an amazing artist; heise from http://heise.deviantart.com/