Jibaku-kun

A planet exists above the sky and below the sea, divided into twelve worlds arranged like a clock, with a central tower where time does not move, known as World Zero. Each world is protected by a Great Child, who is partnered with an explosive, spherical spirit to combat Monster Troublemakers. Bucky, a boy from the first world, dreams of conquering the entire planet and is determined to achieve this goal. He meets Spark, the Great Child of World One, who is searching for a successor. After a brief conversation, Spark selects Bucky as his successor. Bucky becomes a Great Child and is given Jibaki, the spirit of the first world. He then begins traveling across the twelve worlds, accompanied by companions he refers to as slaves, in pursuit of his dream.