Doomsday: I Obtained A Fallen Angel Pet At The Start Of The Game - Chapter 37

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!

In a world where six once-allied nations now stand divided, the kingdom of Myralis, a symbol of self-sacrifice, has fallen into oblivion. Centuries after its mysterious downfall, Caelum, the last disciple of a forgotten deity, embarks on a perilous journey to restore his nation's honor.Guided by the enigmatic teachings of his vanished mentor and armed with the legendary Seal of Abnegation, Caelum must navigate treacherous politics and face champions from rival kingdoms in a deadly tournament that will decide the fate of the world.As ancient secrets resurface and alliances crumble, Caelum discovers that every truth hides a lie and every ally could become an enemy. His quest could either unite the Six Nations—or precipitate their destruction.Will he master his heritage and fulfill the prophecy that marks him as Myralis’s savior, or will his choices doom the world to chaos?

There was a Senior Brother and a Junior Sister. One of them was transmigrated to this world and had cheats while the other was the reincarnation of a Great Emperor.