The Extra's Supremacy - Chapter 19: Catacombs

Violet skies, a world undergoing massive changes, a deficient moon, interlinking voids…
When the world experienced a cataclysmic event,the majority of living things ceased to exist. Although humanity survived by hiding in the last safe zones, humans had to face mutated dire beasts and colossal source beasts that could break through the space barrier and enter the earth at any second.
Luo Yunyang, a young man who grew up in those calamitous times, obtained an attribute regulator and set out to walk the path of supremacy!

- Description from novelupdates

The world is terrorized by the powerful Black Witch who has been sealed in the moon. Every ten years, the night of Hexennacht arrives and a chosen witch must battle the Black Witch in hopes of finally defeating her.

As the current decade’s Hexennacht approaches, a mysterious girl named Kagami Kagami arrives and meets Horinouchi Mitsuru, the daughter of the previous Hexennacht representative.

It takes place between Kyoukai Senjou no Horizon and the City Series, two other series by the author.

The end of the world is full of crises, but Su Chen says not to worry because he has the Red Alert System. That’s how confident he is. You say you have a lot of weapons? Sorry, I have more weapons than I can use here. Let me introduce you to the weather control device. You say the mutant beasts are very powerful? No problem, I have a way to deal with them…

It was supposed to be her sister's wedding night, but she was schemed by her biological mother, drugged, and sent into her 'soon-to-be brother-in-law's' wedding car.When they first met, the man in the wheelchair was as dignified and cold as rumored. Just because she approached him slightly, he grabbed her neck, nearly choking her to death.'A woman marrying into the Fu family must rely on herself to survive, understand?'She nodded frantically, thinking that carefully pleasing him would allow them to live respectfully and peacefully like guests for a lifetime.Yet in the nights and days of accompanying him, she was thoroughly consumed, step by step falling into the trap he had long set.In this life, there is no escape; in this love, it moves the heart.