Millions of years ago there was a war between the Demon race and the Humans which resulted in many innocent lives being taken, till a common enemy appeared and both races had to join forces to prevent extinction. When the danger was taken care of, the heroes from both parties decided to end this meaningless conflict and finely restore peace. From that day onward the "Demon Realm" and the "Human" world were separated in different dimensions and the war was finally over with no traces left behind like it never happened.
Today – The human world
"School Bell rings"
"Ah, finally school is over for today, I can finally relax." – Shiro Tachibana 3rd year high school student.
"WHAT DO YOU MEAN BY RELAXING" – A loud angry voice responded.
"Don't you remember that today you have to help the art club fixing all that mess you caused the other day with your stupid tricks" – Yui Shimizu – 3rd year high school student (Shiros girlfriend)
Shiro: "Ok, Ok, you don't have to yell at me. Jeez right when I thought it was over for the day."
Yui: "Well it's not my fault that you ended up crashing into their charity stand trying to perform an air trick with your skateboard."
Shiro: "Ok, I will be more carefully next time."
3 hours later
Shiro: "And that's all we had. Is there anything else we can help with?"
Art Club student: "No that's all we had you can go now. Thanks for the help!"
Shiro: "No I'm the one who should apologies for making this mess in the first place."
Yui: "Hey Shiro I'm done over here what about you."
Shiro: "I'm done to. We can go now."
Yui: "Ok, let's go. Good night everyone."
In that moment a strange feeling shook Shiros body.
"Shiro Turns rapidly"
Yui: "What's wrong?!"
Shiro: "Nothing I just felt like something was watching us."
And he wasn't wrong, a dark siluete was looking at them from some type of portal.
Shiro Thinking: "That was definitely a strange feeling, but what could it have been about. Ah it doesn't matter now all I want is to go home and relax."
After saying goodbye to Yui and returning home Shiro was faced with another surprise.
"Where have you been it's been hours since you finished school and you come here this late," – Ai Tachibana Shiros mother – "Don't tell me you got in trouble again" – said she with an angry look.
Shiro terrified of his mother's killing intent just told her the truth and prayed for the best.
His mother though angry decided to close an eye this time and left him of the hook.
Ai: "Ok I'm not mad, but make shure this doesn't happen again."
Shiro Thinking: " Yes, I get to live another day there really is a god out there."
Shiro:"Ok I'm headed to my room now so I can rest a bit."
Right after saying that he had an uneasy feeling like some predator was staring at him.
Ai: "Where do you think you're going? Even though I left you off the hook doesn't mean that you are free of your chores. Remember that you had to clean the attic today as you promised since your father will be working late tonight."
Shiro Thinking: "Oh, I forgot about the attic. Everything but that scary old place"
Shiro: "Ok I will start right after taking a bath."
Ai: "YOU WILL START NOW!"
Up in the attic
Shiro: "Ah come on why am I the one in charge of cleaning this part of the house whenever father isn't here. I really hate this place it creeps me out."
"Loud Bang"
Shiro: "WHAT WAS THAT?"
Shiro holding the broom on his hands went to see what made that loud sound.
Shiro: "It's a book! Strange I don't remember us ever having this here."
The book was titled "The Forgotten Truce" which immediately sparked Shiros interest.
Shiro: "I'll finish the attic for now and then I will check this out."
23:00 PM
Shiro: "Well now that everything is done I will lie down and relax since tomorrow is Saturday and school is closed."
Out of nowhere he is shocked to see the book he left in the attic appear right on top of his desk.
Shiro with a nervous look on his face decides to check the book out and is shocked to learn what it had in store for him.