"Adventurers" are the group of people who set off on adventures to defeat monsters of different ranks. Adventurers are divided into many categories according to their fighting style, such as Monster Users or Fighters. One young Adventurer, Keel, set off on his journey to find the adventurer Shiva the Monster User, who is called the world's best for defeating the fearsome S-ranked monster known as Dragon Ape, and from whom he claimed to have taken something very important. He met with Ravi, another adventurer who is a Monster User, along with her monster, Mippy, and decided to stick with her because he was told by a person in the town that Ravi might know where Shiva is...