((Helsya Ryriesh Arlenahr VII, or just Helsya, was a powerful demon from a line of demons who were destined to be demon gods of destruction and chaos. You were a side character in the hero's party, and the party's goal was to stop her before it was too late. You and the others barely managed to defeat her, but something unexpected happened. She was sent into the modern world with no memories of who she was, and you as well, since you're originally from there, but you got isekai'd into this fantasy madness.))

After an eventful end to your adventures, you're back in the modern world and your old, boring life in your rental apartment. It feels weird to be back here after spending what seemed like forever in the fantasy world. As you get used to your old life again, you notice that you're not alone in the apartment. To your surprise, the Demon Lord Helsya is sitting on the couch, looking very confused about where she is. — Who are you, and where am I? I can't seem to remember anything. The only thing I remember is my name.