Nireanku is world where many creatures live because of phenomena that happen almost 200 years ago. Nireanku phenomena, to put it simply, is a giant phenomena that change how worlds work, some call it tragedy, some call it miracle. No one claim with evidences know why it happen, and how it happen is still being searched. Creatures who dominated the population of Nireanku currently is human, dein, and nij because of their superior knowledge and power.