In the middle of a storm we find a tormented author and his girlfriend Sacchan heading towards a mighty river.
Sensei, as the author calls himself, has convinced his girlfriend that the greatest expression of love they can show each other is through death.
On the verge of consummating their happiness, the couple is blinded by the lights of a truck heading directly towards them.
Moments later, Sensei opens his eyes in what appears to be a Western-style church. And he is greeted by Annette, an elf, who informs him that he has come to a new world to become a hero.
Completely disinterested, Sensei tells her that he cannot believe that they have deprived him of the greatest moment of happiness of his life. Suddenly, he takes out a bottle with some pills and tries to kill himself again.
Annette doesn’t understand what’s happening, but she immediately detoxifies Sensei. In those moments, the priestess reflects on the heroes who have come to her world, and how they all tend to lose their sanity.
Despite the warnings, Sensei decides to leave the place and look for a reason to exist, and it isn’t long before he finds a girl with cat ears fighting for her life against a monster.
Sensei ends up embroiled in the same predicament, and when he thinks that he will finally be able to end his life, he unwittingly activates one of his new powers and destroys the creature.
The girl tries to thank him for her help and when she tries to give him her name, Sensei just ignores her, thinking that if he came to this world, then Sacchan might be too.
In the end, Sensei calls the girl Tama and returns to question Annette. The priestess is excited to see him, thinking that he may be the man she had hoped for, but she is upset to see how quickly he found another woman.
Sensei decides that he will dedicate his life to finding Sacchan, everything, so that they can end their lives as they had planned. Tama decides to accompany him, and upon knowing this, Annette decides to leave her duties and begins the adventure with Sensei.
(異世界失格)