Maou-sama no Machizukuri! ~Saikyou no Danjon wa Kindai Toshi~ - Volume 1 Chapter 4

“The world’s not fair, but fairness doesn’t pay the bills. You don’t wait for a handout — you build your own damn ladder, one step at a time.”Ethan Grey’s life was built on ambition, hard work, and hope — until a single accusation destroyed it all.Framed by his ruthless boss, Ethan loses his job, his reputation, and is left drowning in half a million dollars of debt.Cast aside by a society that thrives on crushing the weak, he’s at rock bottom with no way out.But in his darkest moment, something extraordinary happens. A mysterious system awakens, offering Ethan a second chance — but with rules.[Congratulations, You have awakened the Harem Investment System]It can’t make him rich overnight, and it won’t give him shortcuts. Instead, it points him toward physical investments: crumbling properties, broken-down machines, and forgotten treasures.Each one is a gamble, but with every success, the system rewards him with newfound skills and opportunities.

After choking to death on a watermelon, Rong Jiahui thought that she would enter the netherworld and be reincarnated.

But when she opened her eyes, she discovered, to her very horror, that she had returned twelve years into the past…

Looking at the beautiful and awkward “little brother” that would be conferred the title of Marshal in the future for outstanding military service, she almost let out a snort of laughter.

She firmly decided to hug the thigh of this little brother, and climb to the top of her life!

The plan was beautiful, but it had just one problem.

Why had this little brother… suddenly turned into…

A little sister…

- Description from Novelupdates

Seventeen-year-old Grayson has endured a harrowing childhood, leaving him with a dark and twisted philosophy. Driven by this painful doctrine, he imposes his skewed beliefs on everyone and everything around him. His malevolent actions draw the attention of an ancient evil, an entity wrapped in darkness and legend. This being sees in Grayson the potential to carry on its legacy.As the ancient evil begins to mold Grayson for a future drenched in darkness, he finds himself drawn deeper into a web of manipulation and control. Questioning whether he has the strength to defy the fate that has been thrust upon him.Theós, an ancient deity whose origins are lost to time, rules with an iron grip, instilling fear and absolute control over those who dare challenge him.“If it is not within Theós' plan, it cannot be done!”

At some point in the 21st century, the Christian God stopped listening to the prayers of humanity. Monsters with colossal strength and endurance began to emerge and humanity entered its darkest period.