This is a world that is inhabited by both mankind and "fairies".

With the blessings from fairies, invisible beings that bestow all sorts of graces to people, mankind was able to develop civilizations.

However, the blessings can sometimes give rise to distortions. When the power of human desires runs out of control, a monster called "Libidosis" will be born.

In order to combat the threats that Libidosis possess, "Fairy Agency" a specialized security organization that gathers individuals with powerful blessings was born. And in this organization is a member named Shitou Soratarou.

As a member of Fairy Agency, Soratarou works to protect people. However, Shitou Soratarou is just an alter ego of Gertrud. His real identity is a candidate for successor to "Kaiten Council" (World Changing Council), a powerful force of the dark world.

Gertrud hid his true identity and spends his time as a student as Soratarou. He then became acquainted with Kaitou Kazuha and Nishizato Takayuki who belong to Fairy Agency as well and later their friend Sakimoto Yumeka.

One day, Yumeka found out that an extraordinary and powerful blessing resides within her.

Using the power of this blessing, Yumeka transformed herself and decided to use her power to fight for people's happiness and peace as "Fairy Bullet"

Meanwhile, Soratarou who has witnessed Fairy Bullet's power began to make his move in order to acquire her power so that he could secure his position as the successor to Kaiten council.