Arc 1: Counterattack of the Tyrant CEO's Ex-Fiancée (Lucifer x Reader) Chapter 1

You open your eyes one day and find that you're already dead. But instead of Heaven or Hell, you find yourself bound to a mysterious voice ...

[I'm the Secondary Character Grievance Delivery System and now that your physical body is dead we're bound like two fated lovers. Together we'll avenge the wronged secondary characters of every world! I look forward to working with you.]

You're tasked with avenging different secondary characters in different realities. Whether as the scorned ex-fiancée of an overbearing CEO in a cliché romance novel or as a cannon fodder doomed to die in the first five seconds of a survival game, you must work hard.