Superstar From Age 0 - Chapter 624:

Once upon a time, the Devil fell in love with one of the King’s many wives. One night he went to her room disguised as her husband and made love to her. She got pregnant with his child. Knowing this The King ordered her execution believing his wife cheated on him, but then the Devil appeared to the king making him a deal. In exchange for great power for his Kingdom, the King will let his wife Sire The Devil’s Child. The King who was greedy for power agrees to the deal and his Kingdom becomes one of the most powerful Kingdoms and the Devil’s Child, the seventh Prince of the Kingdom.

Unrivaled Spear Knight.

The stereotype that knights must use swords is broken by the brightest star of a duke’s family. The hero that brought an end to the empire’s civil war. The name of that person is Joshua Sanders.

Despite his reputation of being called the empire’s unrivaled spear, he was bleeding dark red blood. Not just anyone but by the hand of his own emperor, Kaiser… “Kaiser! Don’t think it will end like this!!” Moments before death, incurred by magic circle, the spear that spent its years together with him, ‘Lugia’, started to emit an enormous amount of energy…

This familiar place, it can’t be… the stable that I used to live in when I was young?

My body became young?! Lugia, what the hell are you?

Joshua returned to his younger self. His ultimate revenge starts here!

The MC entered the body of the An family eldest son, An Ziran, an arrogant 16 years old boy who weighed 78 kg (~171-172 lbs), who only knew how to eat, play and sleep. Seeing his current body, An Ziran decided his first priority was to LOSE WEIGHT!

Three days later after he became An Ziran, An Ziran’s father and his biological mother died, which meant as the eldest son he had to take over the family business.

Beside his legitimate first wife, An Ziran’s father also married 3 others women, who all wanted to take over the An family fortune but only the eldest son could be able to touch it, therefore they have to depend on An Ziran in order to live a comfortable live.

An Ziran’s father also had an older brother who is always planning to steal the An family fortune. The elder brother of An Ziran’s father and the woman he married had powerful connections. In order to save the An family fortune, An Ziran has to find a golden thigh to cling on. The butler told An Ziran that there is an engagement between the An family and an influential family. Therefore he takes his sister to that family house to make a connection.

However, during their journey, An Ziran’s younger sister overheard that the son of that family is UGLY, so as a beautiful and spoiled young lady coming from a rich household, she didn’t want to marry him and decided to run away. Without any other choice, An Ziran had to take his sister’s​ place and marry that man, who told him that he would let him go soon, but lied.

- Description from Novelupdates

After an unexpected death, a soul finds itself reincarnated into the body of Itsuka Shido, an ordinary teenager in a world filled with powerful spirits, magic, and dangers from other dimensions. With the help of a mysterious system integrated into his body, Shido gains the ability to travel across worlds, summon legendary anime characters, and unlock a wide array of random skills and abilities.Disclaimer: The cover isn't mine, credits to the original artist.