Cinnamon Bun - Chapter Five Hundred and Thirty-Eight – Fortress of Solitude

Ryo Tanaka, a struggling college student, works tirelessly at multiple part-time jobs to make ends meet. In a bid to earn some extra cash, he volunteers for a paid drug research study, unaware that it will alter the course of his life forever.The experiment takes a disastrous turn, leaving Ryo bedridden with a high fever for several days. But when he finally awakens, he finds himself in a world plunged into chaos. A deadly virus has ravaged the city, turning its inhabitants into ravenous, flesh-eating zombies. Streets once bustling with life now lay desolate, the remnants of civilization crumbling under the weight of the apocalypse.

As a promise, he went out into the world as an assassin. 3 years later, after becoming the Supreme Assassin, he gave up on everything he had and returned to the ranks of ordinary people. But one day, Kismet, a mystical game created by the National Research and Development had appeared.

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!

Winged beasts with a hundred-meter wingspan swooped from the skies above.Bloodthirsty creatures weaved and leapt between skyscrapers, in search of prey.Thunderous beasts shrouded in lightning took steps that shook the earth with each stride.Humans hid, trembling in the city ruins, praying for the protection of the World Tree.Outside the city, a gargantuan tree that eclipsed the sun, opened its eyes.“This is the city under my sanctuary. Leave, or meet your death!”In an instant, all beasts submitted.PS: Mutated Animals + Lord genre!Early-stage main storyline: Tame Mutated Animals and establish power.In the mid to late stages, the protagonist can transform into a human.