Choose Tatsuya Shiba's Sister at the Beginning to Become the Tool Person.

There are people, gods, and monsters in this world. Everyone has the opportunity to enter the secret realm, become a powerful magician, and fight against the invading monsters. Talent determines the upper limit of growth, choose success, complete the task, and become the supreme power. The mission failed and turned into nourishment for the secret realm. Jiang Yan, who traveled through time, discovered that the secret realms of this world were all familiar to him. In the secret realm of Seraph, Jiang Yan chose the highest difficulty, killed the ancestor level task, and obtained the magic of this world: eternal life. In the alien world, Jiang Yan killed the alien queen and obtained the invasion magic: corrosion. In the world of Zero Familiar Demon, Jiang Yan killed the source of chaos and obtained the summoning magic: Familiar. In the secret realm, he is like a fish in water. Outside the secret realm, he spoils his sister and fights monsters. This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.