"Since he is referred to as the "Dark King", this could mean he is named after R'lyeh from the Cthulhu mythos."
Cthulhu
https://www.google.be/search?q=Cthulhu,&es_sm=93&source=lnms&tbm=isch&sa=X&ei=gkw9VP7CLIL2aOy-gtgO&ved=0CAgQ_AUoAQ&biw=1280&bih=899#tbm=isch&q=Cthulhu
c'est son ashura à lui 