Haruko Koen is a 17 Year Old Hikikomori who spend most of his days playing games & eating junk food . But all That is about to change very soon as fate have drawn a new path for him .because haruko is going to be reincarnated as a villain in another world , and he will need to help Celestine , an Elf Girl Who Summoned Haruko as a demon lord to help Save Her Sister From The Real Villain Of the Story .