Isekai Maou to Shoukan Shoujo no Dorei Majutsu - Volume 7 Chapter 1 part5

A mysterious natural phenomenon caused the Earth to be plunged into darkness. The world turned into an endless bloody chaos and mankind is on the brink of extinction…

I don’t know why I die, I don’t know why I live.

Divided hunters die of loyalty,

The witch who plays with emotions dies of love,

Cautious fortune-tellers die of trust.

The thief who steals everything has nothing,

The visionary who created everything never existed.

The traveler fell on his way home,

The twilight giants rest before dawn.

Lawyers sacrifice for order,

Judges forget the law.

The sleepless sleeps in the dark,

The corpse collector lay in the coffin.

We are guardians, and a bunch of poor creatures who are constantly fighting against danger and madness.

This journey is life and death.

While drowning was inevitable, they had struggled.

This is the worst of times, this is the best of times.

- Description from novelbuddy

A ritual gone wrong gave him the world's deadliest Class—now all he wants is blood.Zeth stole the most powerful ritual magic in the world from a mad cultist. A Class that's fueled by the blood of his enemies and human sacrifice. One that's illegal to use, punishable by gruesome death. And now that he has it, he's faced with a choice: hide away for the rest of his life from those who would hunt him down, or embrace the power, becoming the hunter to get revenge on the murderer that stole his friends' lives.For Zeth, that's no choice at all.His enemies have to die. And he plans to use every drop of blood, eldritch ritual, and demonic summoning he can to kill them.

Bound together by an imperial arranged marriage, Li Yuyan is scorned for her association with the ill and blind crown prince. Publicly, she stands up for the seemingly gentle and perfect prince, and he in turn protects her from criticism. Privately, she contemplates inheriting a fortune if he dies, while he considers eliminating her if she steps out of line. Unknown to all, the beauty and brilliance they keep hidden will unveil. During their wedding night, as she cures his blindness and cold ailment, but not his secret illness, she discovers the deceit. Realizing she's been tricked, she tries to flee, only to find herself trapped by him as he expresses his fascination with her.