Maou Kurono begins as a peaceful, somewhat intimidating-looking Japanese high school student. However, his life is violently upended when he is suddenly summoned to a dangerous fantasy world by a group known as the Crusaders. Instead of a grand welcome, he is immediately captured and subjected to horrific human experiments at a facility called the "White Sacrament," becoming "Experimental Subject No. 49". This traumatic experience is the source of his kurou (hardship) and ignites his quest for survival.

Ma Kurou serves as the ultimate measuring stick for Kasumi Kenshiro’s growth.

Ma Kurou embodies a rich and complex interplay of void, space, and existential awareness. Its influence spans across traditional and contemporary domains, offering a versatile lens through which to explore the intersections of culture, philosophy, and aesthetics. Embracing the concept of Ma Kurou can lead to a deeper understanding of the balance and harmony inherent in the world around us.