Arifureta Shokugyou de Sekai Saikyou (WN) - Volume 4 Chapter 3

One day every human on the world suddenly receives a mail claiming to enact the World Salvation Project. Half in doubt Kurosaki Shion, a diligent university student and loner, follows the mail’s instructions, becoming one of a million Demon Kings governing his very own Domain in the new world.

*** This is a post-apocalyptic story containing many fantasy elements. It is a somewhat dark tale following Shion as he grows while aiming for the unification of the all too sudden new world. It has many game-elements bolstered by strategical thinking while at the same time providing funny moments and romantic encounters.

"Five years! Do you know how these five years have been for me?"

It had been five years since Gongzi Liang was transmigrated to a fantasy world and had received the Legendary Gold System.

However, the system kept nagging him to top up every time.

[$3 for God's Ring, $6 for first-time reward, $18 for enhancement, $28 for God-tier Beast...]

Gongzi Liang could only look at all the god-tier rewards and couldn't do anything because he didn't have money.

But, he did realize that he could level up his skills and strengthen his body by using copper coins. It could save him 99.99% of training.

It wasn't even hard for him to jump a few ranks in one day.

He would also gain coupons by completing the daily missions.

Just like that, Gongzi Liang became obsessed with completing his daily missions...

…but it seems pretty doable.

Beings that create and control monsters and demons, beings that build and reign over malicious labyrinths, the chosen individuals to possess an overwhelming Unique Skill… They are the Demon Lords.