The Black Book: Seven Deadly Sins - Chapter 59: Prison Break

Humanity had finally ended the war with the Demon Race and sealed them away, forever.However, they now have to face the treat of the Shadow World, an equally dangerous threat to their civilisation under the rule of the Emperor!Facing only misfortune from a young age, Nikolaus Reinhardt never expected anything good to happen to him.But his world completely changed when he awakened as an Ascendant, and accidentally summoned a member of the Demon Race in his house.Just because he messed around with a god damn book!

Kael Veyne was betrayed, hunted, and left for dead in the depths of the Abyssal Dungeon.As an infamous assassin, he was the empire’s deadliest shadow—until the day his guild turned on him.Ambushed in the Abyssal Dungeon, his body was torn apart, and his soul was consumed by the abyss. But death was not the end.He reincarnates 25,000 years later with the Devouring Bloodline System. Kael awakens in the body of a noble scion sharing a similar name to him, and his very essence fused with eldritch power.With every kill, he absorbs primal energy, evolving into something far beyond human. Monsters, mages, mancers, knights, assassins—nothing is beyond his reach.

The whole world is subjected to a highly dangerous standardised exam called the Global University Entrance Examination. Answering questions by putting their lives at stake, they would live if they passed the test. Every month the exam will undergo reformation while, occasionally, it is random.

- Description from Novelupdates

While the demons were rising, mankind was about to become extinct. Six temples rose and protected the last territory of mankind.