MTL - The Strong Beauty is a Goddess in Showbiz - Chapter 445 found it

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

In modern society, a 24-year-old ordinary young man Reid managed to avoid a dump truck and declined the invitation to the reincarnation space, only to be sent to the Marvel Universe by a computer malfunction. There, he obtained the DC role-playing system. As a result, the Marvel Universe got a taste of the darkness from the DC Universe.In order to protect the Wayne Corporation, Alfred pulled the trigger on the executives supporting the IPO.To eliminate the mutant threat, he allowed Jean Grey to be infected with the Joker infection.Captain Marvel, who served as the cosmic police, could never have imagined that the Martian Manhunter, who followed her in fighting against the Kree empire, had been secretly controlling her mind all along.“I am indeed playing the role of a hero,” Reid did not deny this. “However, it's a hero that belongs to me.”When the threat was finally neutralized and the Justice League ascended the podium, people realized they had already been shrouded in injustice.

A Count’s Daughter who lost in the running to become the Second Prince’s fianceé, Camilla. The Prince chose a Baron’s daughter as his fianceé, and the world blessed the two’s love as fated. On the other hand, Camilla who was tailored and elevated as the love’s villain in the end, as punishment she was made to marry a terribly fat and ugly man――called『Toad of the Swamp』from his appearance, a lord of a remote region named Alois.

It was in the year 2800 of the Midgard calendar. Back then, there was a Overlord who once reigned supreme and had reached the very brink of subduing the world.