I Became a Plutocrat in World War I: Starting with Saving France - Chapter 3: After modification - Everything is a Transaction

Roy’s life was nothing special. The only thing commendable was the last few moments when he saved a mother and her child from a drunk driver.
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It’s really an egg! Damn it, what kind of monster have I become? Did I fall into Hell instead of making it to Heaven??
Join Roy as he ventures through various worlds with the Custom Made Demon King System—a system that allows Roy to draw anything he can imagine and create it through exchanging souls!

Ace had always harbored feelings for his childhood friend, only to have his heart shattered when he learned she was secretly in love with Duke. The betrayal left him disheartened, but nothing could have prepared him for what came next.That night, instead of waking up to another ordinary day, he opened his eyes in a completely different world—inside another man's body. Worse still, the first thing he heard upon waking was yet another rejection.Thrown into an unfamiliar land with a past he doesn't remember and a future he never planned for, Ace faces a choice: chase after love once more or embrace a new passion—one that comes in the form of an unexpected farming system. As he cultivates spirit crops and reaps rewards beyond imagination, he begins to wonder: perhaps love isn't found in a person, but in the soil, the growth, and the endless possibilities of the land.Will Ace sow the seeds of a new destiny, or will the echoes of rejection root him in the past?

An angel made a mistake, resulting in Shiihara Daiki’s death. In order to hide the mistake, he was then sent to a different world. The angel will grant him one wish as a payment for keeping it a secret. Daiki asked for a Heavenly Castle floating in the sky without hesitation.

Suddenly a floating castle appeared in the new world, which causes confusion amongst the people. They attempt to contact Daiki in various ways. A country tries to steal it by force, while another seeks to befriend him. What in the world would Daiki do?