Reincarnated Lord: I can upgrade everything! - Chapter 75: An Alliance

I reincarnated as Luna, a supporting character who is accused of ruining the heroine and hero’s relationship, and is mu*dered. I’m not interested in someone else’s man, but the heroine’s friends bully me every day. “Why are you trying to get close to someone who’s already taken?” “That’s right, please stop! Why are you doing this?” “Stop doing such terrible things!” So Luna decides to announce it in front of everyone. “I don’t want someone like Fersen even if you beg me to take him so stop bothering me. I’d rather date Anthes Vincent, who’s rumored to be insane.” And soon she meets someone who she never expected to meet…… “I heard you have an interest in me? The truth is, I do too. Is it a coincidence?”

The end of all worlds approaches.

The Demon King Order harvests lives from all manners of living beings.

Within this darkness full of despair,
A single person escaped from space-time, returned to before the world collapsed, determined to change the fate of the past.

But as time pass, he gradually finds out that the Apocalypse isn’t quite as simple as he thinks…

- Description from novelupdates

One day, I woke up only find out that I’d become a Demon Lord, an individual responsible for protecting a dungeon. The world I’d been spirited away to was one filled with violence. Gigantic monsters wandered through it and competed with each other each and every day for the right to survive. I had no choice but to strengthen my dungeon’s defenses in hopes of living another day—or at least that was what I’d thought. For some odd reason, I instead ended up spending my days in relaxation and bliss.