The Black Beast’s Useless Concubine - Chapter 48 - : Chapter 48 a conspiracy!

Xiao Ze, who was dedicated to the people and vowed to become a generation of Ming Jun, accidentally fell on a little lady.
The little lady was born beautiful and lovable.
So Xiao Ze accepted his life and got the name of fear.

ps:
①The male protagonist has no concubine, and he is dedicated to serving the country.

- Description from novelbuddy

After dying in an oddly anticlimactic vending machine accident, Kazuki Ren is reincarnated in the demon realm—not as a hero, not as a villain, but as the only human male student enrolled at the mysterious Academy of Ruin, a school where all the professors are demon lords and all the students are powerful, beautiful she-demons.Ren is told he has one task: survive.But there’s a catch. The Academy’s darkest secret is about to awaken, and Ren holds a hidden power that could either destroy the demon world... or rule it.Now surrounded by seductive demons with hidden motives, eldritch tomes, forbidden dungeons, and twisted exams, Ren must master his ability—or be consumed.Magic, mystery, danger, and temptation await in this dark academia harem fantasy.

The world was consumed by a vile corruption brought from beyond – the sun dimmed, and life as we know it was almost extinguished.And yet it was not the end but merely the beginning.Long after the disaster, a lone survivor awakens with a newfound power to wield the divine flames and many questions about the past. He embarks on a long journey to burn the rot away, discover what's left of the old world and maybe, just maybe, ascend to divinity.

In the current era, people are either normal or are with ‘special abilities’. Cases related to the latter are managed by the “National Anomaly Prevention and Control and Special Species Management Office”.
Qi Zheng Emperor Sheng Lingyuan was reawakened a thousand years later after he jumped off the fiery Red Lake. Xuan Ji, a newly transferred staff to the Reparations Division of the Deviant Control Office, finds himself having to clean up the mess of a revived tyrannical monarch. The two seemed to share something from the past, but unbeknownst to them, a big conspiracy is stirring right underneath their noses that could destroy the balance of the world.

- Description from Novelupdates