In a world where witches have declared war against humanity, two-thirds of the world falls under their control. The surviving human population gathered specialists with the power to track and destroy witches and called them Witch Hunters.
Tasha Godspell, also known as the "Magic Marksman," is one of the best hunters there is. Along with his sword-wielding Jack-o’-Lantern partner known as Halloween, Tasha puts his magical training and weaponry to good use, in his constant battles against witches. And yet, he cannot bring himself to fully hate the very witches he is tasked to destroy.
West (웨스트, Weseuteu) is one of the Four Great Witches and the witch said to be the strongest of all time. Although a pacifist, she once fought against Mordred and defeated her but West was eventually defeated and killed by the combined force of North and South prior to the Witch-Human War. North is currently trying to revive her; however thanks to the Death/Rebirth powers of East who bypassed the normal laws of Karma, West was reincarnated into Tasha Godspell.
Edea loses control of her emotions resulting in her inner world-self taking control. Edea admits that killing Aria may suppress her negative emotions, but only temporarily. Edea laments that she only wanted to feel the warmth of being with Tasha and the consequence for this is too great.