This is a world where humans and animals coexist. In AD 2315, the "Original Beast Tide" swept across the world, and human civilization was almost destroyed. The survivors discovered that they could fuse with a mysterious "natal card" and summon a pet beast that would accompany them throughout their lives. Since then, mankind has completely given up on technological weapons and embarked on a new era centered on beast control.
Here, everyone can control beasts, but talent determines the starting point. Pet beasts continue to grow through fighting, training, and evolution - in theory, the road to evolution has no end. Some people have trained the Blazing Dog to the 100,000th level and transformed into the Burning Sky Vulcan; some people have made the Rock Turtle evolve a hundred times and become a moving mountain fortress. But it all started with that sixteen-year-old boy and his mutated natal beast.
