Mysterious cases keep occuring in Zeropolis, a futuristic city. Tomoe Rena who coincidentally got involved in one of those cases met a girl who was fighting a herd mysterious monsters. The girl name is Erika, and during the incident, Encielium card in her possession reacted to Rena's hidden power.

Rena was transformed "Enciel Rena" and she was able to force the monsters to retreat. After the fight, Rena invited Erika to stay at her house. There, Rena learned the existence of the invading kingdom from the other world, Azahyde, and its intention to overrun Earth with the monsters from Erika. With her power being awakened, Rena decided to join the fight.

However, Rena, whom the prince of Azahyde fell in love with at first sight, fell into the traps made by the monsters, and her pure innocent body started to be corrupted by pleasure. Still, Rena chose to continue to fight for her peaceful town, school, and friends while she suffers through the humiliations...

[Translated from Getchu]