Asta and Yuno were abandoned together at the same church, and have been inseparable since. As children, they promised that they would compete against each other to see who would become the next Emperor Magus. However, as they grew up, some differences between them became plain. Yuno was a genius with magic, with amazing power and control, while Asta could not use magic at all, and tried to make up for his lack by training physically. When they received their Grimoires at age 15, Yuno got a spectacular book with a four-leaf clover (most people receive a three-leaf-clover), while Asta received nothing at all. However, when Yuno was threatened, the truth about Asta’s power was revealed, he received a five-leaf clover Grimoire, a “black clover”! Now the two friends are heading out in the world, both seeking the same goal!
The show revolves around Ichigo Kurosaki, a good-hearted 15-year-old high school student who carries the undesired ability to see spirits. Others in his family (two sisters and his father) carry this ability to some extent as well. One evening, he encounters Rukia Kuchiki; a Shinigami, or Death God. It is her job to usher lost spirits to Soul Society, and to also eliminate those which cross over from the Hollow World.