Local Netizen Elf's Life In Another World - Case 296: End of friendship.

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.

As a wandering soul trapped in endless cycles of reincarnations, Claus must decide what to do in his current life.

Sergeant Xia Yao, born into a wealthy and renown ancestry, is a playboy who has turned over a new leaf. Yuan Zong is an ex soldier from the special forces who opened a bodyguard training company after being discharged.

When Yuan Ru, Yuan Zong’s sister fell for Xia Yao’s charms, but could not break down his erected barriers, she came to Yuan Zong for assistance. Little did she know, the moment Yuan Zong saw Xia Yao, this ex-special force knew no other person would ever catch his eye.

And so begins the battle between brother and sister for the most coveted price – Xia Yao’s heart.

- Description from Novelupdates

Kai of the Sorcerer’s Tower is one of the last mages left, barely surviving in a world ruled by creatures of the dark — where the era of mages ended, and most of the lands got contaminated with dead mana. To save his world and fulfil his master’s last wish, he put himself through a forbidden ritual, risking his soul being ripped into pieces to make his way into the past. In an era with abundant mana — an era yet to enter the Golden Era of Magic. Things go wrong, of course, as they always do, and he finds himself thousands of years before the world fell to mana contamination — in the body of a young lord, Arzan. All is not well, though, as the young lord was murdered by someone right at the cusp of a beast wave threatening the territory, while larger threats loom on the horizon. There was a lot to do for Kai to regain his former strength in this time of primitive technology, but then again, he might just be able to change that.