Storyline
Tetra is a low-level adventurer exploring a dungeon when she discovers a mysterious sealed chamber. Inside, she encounters Mart, the former Demon King, whose physical body has long since been lost.
Mart asks Tetra to help him break his seal. Once freed, he proposes an unusual plan: he will give Tetra his power and turn her into the hero capable of defeating the current Demon King.
Tetra initially lacks the strength needed to fight powerful enemies, while Mart possesses overwhelming combat abilities but cannot generate the magical power necessary to sustain them. Their abilities complement each other, forcing them to work together as they begin their journey.
As they travel through the fantasy world, players can switch between the two characters to trigger different events and progress through battles. Tetra gradually develops her abilities while Mart remains a powerful force, and their unusual partnership becomes central to their quest to defeat the current Demon King.
The outcome of certain events and adult scenes can change depending on which character the player controls, adding additional variations to the adventure.