The Yu Brother's Case Book - Volume 3 Chapter 4

A girl who calls herself a demon appeared before a timid student named Fumio Kijima. The girl claims to be a campaign girl from the demon world and she gives him the ability to “summon a room” from nothing but thin air.

At first he doesn’t abuse his power and uses it as a convenient ability in his every day life. But one day he is bullied by his classmates under a false pretext and is made to suffer. In the past he would have wallowed in misery and cried himself to sleep, but now he had a power to call upon.

“I will make them regret it!”

Using his powers to summon his “room”, he begins his era of confinement and brainwashing to achieve his goals.

She had never been real to them.“I never thought of you as my wife.” Even her husband by contract,“My wish? It’s for you to disappear.” Nor the son she didn’t share a drop of blood with.Daphne decided to give up everything then.The Madam disappeared. To be precise, she disappeared before the Young Lord’s birthday, leaving only a single letter. Everyone didn’t mind and thought that she would be back soon.One day, two days, ten days.The Madam didn’t return, and everyone went looking for her. But it was already too late.

She was reborn back to 11 years ago, when everything was fine, her family was still alive and she had not experienced the pain of destruction. Since she had the chance to restart, she decided to seek revenge on those who had hurt her! She would also leverage her knowledge and strength to lead her family to a prosperous life. However, she has a regret: despite being reborn, she still ended up marrying him, a man who was difficult to approach...

“Obtaining the topmost degree of talent in sword arts in the world requires giving up 72 years of lifespan, which leaves you with only five more years of your life. At the same time, you will never be able to feel love, kinship, and friendship, and you’ll end up leading a lonely life until your death, unable to procreate, or to have any descendants.

“From now onwards, everything related to happiness in the human world shall no longer be of your concern. Are you willing to accept this?”

“Hahahaha, I’m already alone bereft of all support, my hopes dashed to pieces, shouldering only absolutely irreconcilable grudge and hatred, why would I disagree? Why would I not want it? I couldn’t ask for anything better!!”

His sword sweeps across the Divine Continent for seven days and nights, moving 90,000 miles through the starry skies, unhindered.

He slays saints and buddhas in Heaven, slaughters demons and devils in Hell, sweeping away all the grievances in his heart!

- Description from Novelupdates