Even though it is an Eroge world, their won't be any stats or levels but magic cultivation.
Rank 1 Sphere
Rank 2 Jewel
Rank 3 Crystal
Rank 4 Core
Rank 5 Gem
Rank 6 Treasured House
Rank 7 Mystic Range
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Rank 8 Mythic Continent
Rank 9 Legendary Continent
I will explain the cultivation in future chapters, but these are the ranks of mortal plane.
There are three plane known to the world.
Infernal Plane
Mortal Plane
Holy Plane