MTL - I, Luffy, Awaken the Sun God on the Top - Chapter 5

Anyone who could construct a stable Spell Model could become a Wizard — that was the Wizards’ ultimate secret! Having been given a new life as the son of an aristocrat and armed with a super quantum computer from his past life, Spell Models came as easily as breathing to Merlin. With this overwhelmingly huge advantage, would Merlin become the greatest Grand Wizard of all time?

Ruins stretched across the landscape in the apocalypse after the nuclear war.

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!