Space and Rebirth: The Favored Genius Doctor and Businesswoman - Chapter 24 – Getting A God-Grandpa (多个干爷爷)

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 scum’s or villain’s long road of transformation was tentatively set to the world:
The abandonment of the educated youth’s wife (Completed)
The hidden marriage of the scum film emperor (Completed)
The best brother in the world (Completed)
The Phoenix male who destroy the bridge after crossing the river (Completed)
The treasonous general (Completed)
I’m an honest man (Completed)
To become the top scorer in the School of Agriculture (Completed)
The soft rice man’s self-cultivation (Completed)
The whole world is reborn (Completed)
I want to survive on a desert island (Completed)
The stallion male who has seized the opportunity (Completed)
The perverted self-salvation (Completed)
The spring of the loafer (Completed)
The misplaced life (Completed)
The miser career (Completed)
The ghost is out of feeling (Completed)
The Queen’s favorite husband (Completed)
The vicious girl with her godfather (Completed)
I want to be a good person (Completed)
I does not tear up the family (Completed)
The perverted common plant (Completed)
The Mary Sue’s men (Completed)
Every time I was reborn, someone wants to kill me (Completed)
The old people’s counterattack path (Completed)
The global evolution (Completed)
When I became a net red (Completed)
For you, good person (Completed)
His heart had white moonlight (Completed)

- Description from Novelupdates

Ye Fan accidentally obtained a billion crystal technology system, and since then, he has become out of control.

Android: You do n’t even have a mobile phone system. I want to make it impossible for you all!
Ye Fan: Sorry, I researched it out, it seems to be more powerful than yours!
BMW Benz: Our engines are famous all over the world!
Ye Fan: Sorry, I do n’t have an engine, I only have magnetic levitation, and the speed is only a few times that of yours. Do n’t worry, take your time!
…
Enemy: Is he still human?
Who can stop this!

- Description from Qidian

In a magical medieval world, it's difficult to hold on to one's beliefs... even maintaining one's integrity is a challenge.Because the commoners here are not simple; they are ignorant, greedy, and cruel.Because the nobles here are not noble; they are insidious, ruthless, and tyrannical.However... not all human constitutions can be generalized.Lann touches the two hearts and three lungs beneath his chest.He estimates that not only in this world but also in the other worlds connected through the convergence of celestial spheres, he can maintain a healthy sense of morality.—And then get rid of all the incorrigible scum!