Reincarnated In My Favorite Novel as The Useless Prince

The story follows a beautiful teenage boy with white hair, who hides behind the facade of mediocrity.

He lost his parents at a young age before being adopted by his best friend's family. He fell in love with his now new step-sister, who was two years older than him and had a severe illness that made her weak and fragile. She was the scapegoat of her family, while he became the golden child. He took care of her at the age of 7 when he was 5 and they fell in love and became a couple at the age of 11 and 9.

Tragedy struck when their family killed her when she was sixteen. He was consumed by madness before controlling that madness and taking down the very same family that adopted him, who happened to be an empire of a company dominating every industry, and destroyed everything two years after her death when she was supposed to be 18. After killing everyone besides his best friend before, he was reincarnated into his favorite novel as a side character better known as the useless prince who wasnt actually a prince but was just beautiful as one.

The story follows his journey as he uses his future knowledge and the help of his system to traverse the obstacles in his path while fighting against the dangers of the world, which is both similar and dissimilar to what he once knew. He must find out the mystery behind his reincarnation and overcome all the crises that are about to happen in the future.

Will the future event follow the same route as described in the novel? Does the world have other plans for him? Is his reincarnation just a coincidence, or does someone or some other forces have a role in it? Follow him as he discovers the answers to these questions and more.
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Reader Disclaimer :
There are two MCs in this story.
1. The original MC of the novel/book
2. The author that transmigrates in the novel/book
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