I Secretly Develop Myself In The Demon World - Chapter 29 - : Life Stealing, Stealing Heaven

Yo, Hi! I’m Frank, I made a deal with a demon to pay me some money for receiving a guest for a few days every week.
I had no idea about what I have done.
On May 1st, Conan ‘the God of Death’ came to my house. I was forced to let him in and we get involved in a criminal case.
On May 8th, Bruce Wayne ‘Batman’ came to me. I was forced to follow him to fight crime.
On May 16th, Hannibal Lecter, The Silence of the Lambs, came to my home. I can only say that I really can’t stand my guests.

- Description from Novelupdates

When people pass away, they often leave behind unfulfilled wishes. I will act as a force of justice, helping the deceased achieve their final desires before I return to my own world to confront and make peace with my own regrets.

Zhou Rui had just turned 20 when his life took an unexpected turn. He was hit by a truck one day. Just as he was convinced he was about to die, something strange happened. Instead of waking up in the afterlife, he opened his eyes as a baby. Later, he learn he had reborn as Lumien Ofnir, the youngest son of a baron.As Lumien grew up, he realized this world was nothing like Earth. Magic was real, and creatures like goblins, orcs, dragons, titans, and other mythical creatures were part of everyday life.Fortunately, in this dangerous world, Lumien received another blessing. It was a system.Follow Lumien's journey as he begins to explore this new world with the support of a Harem System. The mysterious cheat that allows him to copy and develop the magical powers of any woman he has slept with.[Author’s Note: The earlier chapters might feel slow and boring, but I promise it’ll all be worth it once the pace picks up.]

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.