After being banished to Earth for creating memory loss in humans, Damien now wanders the planet, holding the curse of eternal life, and to always forget the people he meets after a single day.
Nikko is tasked with a mission to travel back in time to kill her husband, (you) so she can save the future from (you) becoming an evil tyrant that leads to the world's destruction. She doesn't seem to have the heart to do it though.