Harry Potter: Dimensional Wizard - Chapter 578: Saber's Wish

After the nuclear warfare, massacres started to spread throughout the entire world. The order between humans completely collapses, and the strong eats while the weak gets eaten becomes the #1 rule.

She fought in the Battle of Changping and witnessed the killing of hundreds of thousands. She once led the Qin Iron Calvary and battled against the Six Kingdoms. She has seen a third of the land and witnessed the breaking of mountains and rivers. The sound of a grand zither and the light of a great female emperor. A prosperous world that was forged on the battlefield. Yet, these two thousand years are forgotten from history.

- Description from Novelupdates

There are a total of seven sins, and a revelation is made to a young man named Alex that he is destined to become a demon lord, more especially a demon lord of sin called LUST.

It's not like he can change that and because he always knew something about himself was different—not in a physical sense, well, maybe a little—and not in a mental sense—but rather because he is thrown into a demonic war that compels him to accept his new reality.

He was only aware of a difference in himself. Relating to him and the ladies who are drawn to him... Well, it was more or less like he was a magnet in front of all the girls, and all the girls were drawn to him like a metal.

She became the nanny of Claude, the blackened male protagonist who would destroy the world. If this continues, she will be killed by the cursed power possessed by the blackened male protagonist. So, she decided to pour out her love for the blackened male protagonist to prevent the blackening. She also raised the child’s self-esteem, and made the Duke act like a proper father, as fatherly love was essential for the male protagonist’s self-esteem. She thought the child was gradually recovering his bright face, and the Duke was now learning how to gradually give love to the child. But she doesn’t know if it’s because she worked too hard….? “It has always been a problem. You have hundreds of reasons to abandon me, but I don’t have a single one.” “Nanny will always be by my side, right? That’s why you can’t go. Never, never.” Two men started obsessing over me.