Darkness brings LIght

Two people are reincarnated from earth to a world of magic and swords , One as a Devil to bring destruction while other as a Hero to save the world they both are given a wish and a system ... but what will happen if their role is reversed . novels is both from the perspective of hero and the demon king . so you can see both hero's adventure as well as demon king's dungeon building ********************** ********************** this novel will be unique from other isekai novels. if you find any errors please mention them in the comments [humans tend to make mistakes] read atleast a few chapters before dropping as few chapters will be focused on world building my 1st novel hope you guys enjoy