Apollo Genesis (アポロ・ジェネシス, Aporo Jeneshisu), is the heir to a successful American business company, and is traveling the world before being instated as the head of the company. He meets his Mamodo Rops (ロップス, Roppusu) on the way and they begin traveling together and defeating Mamodos when challenged. When traveling to Japan, the pair battle and befriend Zatch Bell and Kiyo Takamine before leaving. Apollo after some time decide to meet up with Kiyo to tell him what happen in one of his travels. In Holland, they encounter Zeno Bell and Dufort and are defeated with Rops' book being burned. After the pair's defeat, Apollo returns home to run the company and uses its resources to assist Kiyo and his friends whenever possible.