Adam and Eve are the two main characters in the film. Adam is a dark, romantic, and possibly suicidal character who always has the convenience of blaming the humans, a.k.a. zombies, for his misery. Eve is a curious, loving, and appreciative character. They both live on opposite ends of the world but they have been in love for a few centuries being that they're vampires. They balance each other's energies and understand one another.
The characters are based off of Mark Twain's last novel, The Diaries of Adam and Eve.