Supreme Harem God System - Chapter 1819 I will be in your care.

Liu Ling, an unmarried activist, has been unrestrained all her life. Before her death, a friend asked her if she had an unfulfilled wish, and Liu Ling replied she could not raise a baby.

The friend fell into trouble; this is not easy to do. Not waiting for her friend to speak, Liu Ling said that if she gave birth to a child, the mother would die, and her child would live, so let’s forget it.

Unfortunately, God heard.

After her death, she did not enter the underworld and transmigrated into Song Zhaodi. She also had seven children, all of whom were not her own.

- Description from Novelupdates

Summoned after an unfortunate accident in hopes they could protect the world from a coming threat, Ben and his classmates are gifted another chance at life. With fame and fortune promised to whoever is willing to fight for the sake of the world it doesn't seem like a bad deal, there's just one small problem. Ben wasn't blessed with any magic or combat skills, just crafting and enchanting. While the skills themselves aren't useless they also aren't seen as being necessary to the coming war. Now not needed and alone Ben tries to find a place in the world while meeting some of its colourful characters along the way.

He crossed over to a new world where humans have magical power. They are called warriors. They use their power to kill the monsters that appear out of nowhere. Dragons, Dungeons, and Magic users are pretty common in this world. If you want to live in peace, you need to have that power. You can also become a powerful clearing dungeon.

In this dangerous world, he has a system that can help him grow stronger. But he didn't want to be a high-profile warrior who attracts much powerhouse attention or become a lab rat. He wants to be Low-profile and grow strong using his system.

Once through the pirates, Lu En became the son of Monkey d Dragon, a grandfather named Monkey d Karp, and an unreliable and neurotic younger brother named Luffy.

Fortunately, the ghost back system is activated!

The completion of the ghost back is 10%, and the training effect is increased by 100 times!

The completion of the ghost back is 20%, and the training effect is increased by 1000 times!

…

One day, Lu En, a ghost-backed master, appeared in front of Luffy who was shouting to go to sea, and made Luffy cry on the spot.

Luffy: “The pirates in the sea are all monsters like my brother? I don’t want to go out to sea!”

Garp: “For a long time, the two boys, Long and Luffy, with small arms and calves, I really doubt that they are not my sons and grandsons. Like Lu En, they are the grandsons of the old man!”

Warring States: “The strongest creature in the sea, land and air is Kaido? No, it’s Lu En!”

- Description from novelbuddy