Love Story of an Angel and Devil

An angel named Fionna was tasked to go down on earth to fulfill her mission that God gave to her, until she found out that she is not the only supernatural down on earth. A demon, also has a mission on earth was send to destroy humanity. Their paths always collide in human world, every bad thing happens brought by misfortunes of Zack, the demon, to the people, there will be an Angel Fionna that saves the people away from harm and opposes him until... the unexpected happen, they fall in-love with each other. Lots of trials came to their life just to fall them apart because of their forbidden love. Does love really conquers everything? Will they be able to be each other weather it cost them to be mortals? Will they be able to have a happy ending? Let's Find Out...