Fall into Darkness:-

　I had just snuck out of school and returned to the mansion.

"...Now then."

　I took out a notebook from my room.

　The contents of this notebook are very simple. Using the knowledge I have of my past life, I have written in Japanese the plan to prevent my sister from falling into the dark side, and the progression of that plan.

　Naturally, the language used in this world is not Japanese, but something unique to this other world.

　If you write it in Japanese, others won't be able to figure it out by looking at it.

"...When I was zero years old, it took me a long time to learn the language of this world."

　Remembering my past language-related struggles, I opened my notebook.

"...I guess I'll start by sorting things out."

　First of all, the fundamental reason why my older sister fell into darkness is that our mother was assassinated, and it was largely a desire for revenge.

　And the person who did this was the head of this country - the King.

　Before we explain why, let's start by saying that the history of the Kingdom of Yunorechit has always been marked by bloody battles for the throne, and even before the current king took the throne, he had created a bloody drama between him and his younger brother.

　The younger brother, the person in question, has already been imprisoned as a criminal...but now there is a group within the country that wants to free him.

　The reason for this is that the current king made an unbelievable mistake in relation to the war with another country, which caused a lot of backlash.

　The country is in a bit of turmoil right now with the leadership at the top.

　So, you may be wondering how my mother and my sister's mother were involved in this struggle for the throne, but the reason is simple; my mother was simply a member of the royal family.

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　Furthermore, during the battle for the throne, my mother was not part of the current king's faction, but rather belonged to his younger brother's faction.

　The king, the head of the country, has chosen to target my mother, who can be easily removed, as a first step. It can be seen as a measure to reduce, even if only a little, the influence of her own brother.

　This was really easy, because she had easily convinced my father, Margrave Reinhard. Since his relationship with my mother was a purely political marriage, he was able to skillfully explain the pros and cons and get him to ignore the assassination plan.

　In that situation, it was only natural that my sister directed her desire for revenge towards the country itself.

　In the game, Onee-chan is contacted by revolutionary forces who are dissatisfied with the current monarchy, and her ideology quickly shifts to the anti-monarchy side, becoming radicalized and leading a rebellion as the leader of the revolutionary army.

　Here, Onee-chan is defeated... but she still survives and now receives contact from the Demon King's army.

　Demon King's army.

　He's already very popular as a villain in games. He's the classic villain.

　The army is led by the Demon King, the king of the demons, who are fundamentally different from humans and whose nature makes them the enemy of mankind.

　The game's protagonist ends up fighting the Demon King's gang and my older sister at the end of the story.

"Even if you somehow manage to escape with your life, Arc-kun will be in trouble from this point onwards no matter what."

　Arc flees the country when his sister rises up in rebellion as the revolutionary army, and one of the branching routes in the story allows him to avoid execution.

　But even if he flees the country, the fact remains that his sister is a member of the Demon King's army, so no matter where he goes he will eventually be persecuted and basically killed.

　In the best case scenario, he joins the Demon King's army with his sister and gets killed by the protagonist.

"When I think about it again, it seems hopeless."

　Somehow it's all pretty pathetic.

　So, that was the desperate situation I was in, but basically what I did to make my sister succumb to the darkness was to first try to prevent the assassination of our mother, which was the starting point of it all... but this was a complete failure.

　Next, your older sister is contacted by revolutionary forces.

　What I was doing now was to prevent this from happening.

　As long as your sister doesn't lean towards the anti-monarchy side, everything will be fine for now.

　It remains to be seen how best to deal with the domestic turmoil from here on out.

"For now, it's done."

　We have been successful in keeping these revolutionary forces away from my sister.

　During this time I have been working to heal my sister's emotional wounds and to stop her desire for revenge from getting out of control.

　Both my sister and I know that my father sold my mother, and the relationship between our family members is currently at its worst.

　In that environment, my sister and I basically lived together.

　During that time, I hoped that my sister would forget about revenge as much as possible and enjoy the present!

"I was just trying to treat you like a normal little brother, you know...?"

　However, She always treated me as her a younger brother.

"Why did it become so distorted...?"

　What is my sister like now?

　Unfortunately, she ended up with a terrible sibling complex and ended up being even more isolated than I was at school.

"Why?"

　That's strange. I thought she would be more sociable.

　However, there is no way to correct course now.

　I feel stuck.

"Damn... As expected, I couldn't do anything today either. I thought that if I thought about it every day, some kind of plan would come up, but nothing has come up."

　My daily routine.

　My routine is to look back on my sister's past and pray that I can come up with a groundbreaking idea to help her resolve her current extreme sister complex.

　I cursed myself for not getting the results I wanted from this routine again today, and just closed my notebook without doing anything.