Synopsis: The Devil Is Troubled by the Suicidal Heroine!

After feeling hopeless about her life, high school student Mana takes her own life. But she's reborn in a new world as an indestructible female hero. However, Mana cannot accept living forever and embarks on a dangerous quest to find a way to break her immortality at the Devil's castle. Despite the Devil failing to kill her, Mana threatens him with the words, "If you can't end me, I'll end you." This unconventional and thrilling series follows her pursuit for ultimate peace from her eternal existence.