Arifureta Shokugyou de Sekai Saikyou (WN) - Volume 2 Chapter 4

Hyde arrives in a doomed world with nothing but his body and fragmented knowledge of the future from a game he once played. He has no grand ambition—why try to save a world already destined to fall? Survival is enough.That is, until he discovers his sister is also transported into that world.However, only he hears the Melody of Nightingale and receives the power to survive.[You have established a connection with The Forgotten Hollow.]Awakening as a Resonant—an elite group with supernatural abilities—he is thrust into a conflict between two worlds. Armed with the authority of space and time, he vows to protect his powerless sister at all cost, even if he has to fight against the Mirage creatures, other Resonants, or even Gods themselves.

The formless ancient world was infested with despicable demons. They hunted and feasted on mankind, keeping the human civilization constantly in a weak and suppressed state.

During the first known year, a magical mountain descended into the world from the realm of the Gods. Carved on this enormous mountain was a message: ‘Heaven Prevails’…

After the Grand Descent, a name that was given to the descending of the mountain, the Three Great Sages made their ways to Mystic Mountain where they learned to harvest what we now call magic, establishing the Mystic Cults and eighty-one sacred shrines to help aid mankind with the cult’s mystic powers against the eternal fight to the death with demons.

- Description from Novelupdates

After her rebirth, Rita vows not to repeat her past mistakes. This time, her first priority is to stop her brother, who is about to marry into the Lopez family, from participating in the initial game beta test. In her previous life, she was deceived by this scheming brother until her dying breath. It was only at the end that she realized she was merely a villain in a male-oriented novel about a live-in son-in-law, with all the malice and manipulation orchestrated by him behind the scenes. In this life, Rita decides to change the rules of the game. She will stay in the shadows and seize all the opportunities meant for the male and female leads. By participating in the beta test and re-selecting her abilities, she systematically dismantles the protagonists’ advantages, all while making them believe she’s on their side. Rita has no intention of harming innocent people, nor is she a selfless saint. In this game, she works with the authorities for mutual benefit, all to achieve her ultimate goal—becoming the true master of her fate.