Start in DxD as Motohama: Leveling Up in Another World - Chapter 10: Another World (I)

"What you do in life, Echoes in Eternity."

The System, who goes by the code name, Thirteen, defied the System God in order to give his previous Hosts’ the chance to change their Fates.

Unfortunately, he was killed by his Father, the System God, and was sent to the world of Pangea to struggle like the Cannon Fodders that he fought so hard to protect.

Armed with his knowledge as a System, Thirteen vowed to change not only his Fate, but the Fate of others whose destinies were tied up with him.

In a world torn by power and corruption, a fallen System will bring out a symphony of change, or lead it to its destruction.

When he was categorised as an Omega at the age of 13, Rong Yi made a tiny little wish. In the future, he wanted to fall in love with a tall, handsome and elegant Alpha whom he could share a romantic love with, then build a blissful family with him and give birth to many cute babies together.

A few years later, he grew into a tall, handsome and elegant Omega and was passionately pursued by countless admirers of the same gender, while all Alphas backed away from him in face of his superiority.

This was not the life he wanted.

- Description from Novelupdates

In order to live he must get close to girls, what kind of rule is this? Tang Zheng possess the Nine Yang Saint Body, a rare body constitution that is hard to come across within a millennium, yet he must absorb pure Yin energy to stay alive. In order to live, he will fight! Absolute campus belles, goddess teachers, charming housewives, haughty lolis… all kinds of woman walk into his life causing him to be surrounded by beauties!

- Description from Novelupdates

“I will have my vengeance, in this life, or the next!”Albedo died alone and depressed and was reborn in a Novel he had been reading. However, instead of becoming the Protagonist or Antagonist, he becomes Albedo Neverwinter, an Extra he couldn't even recall from the Novel.However, the cruelty of life didn't change even after rebirth, and his new family was ripped away from him, leaving him with nothing but scars as reminders of the gruesome fate his family faced.Promising to get his revenge, watch as Albedo, alongside his System, his tactical mind and scarce but valuable future knowledge, rises up the ranks and ascends the pyramid of power.[ OP MC, System, Harem, Romance ][ Yeah there will be Smut, but it won't dominate the Novel ]