The Dark Rebirth of Pandora: Revenge of the Abyss - Chapter 25: How to learn Magic

A man suddenly finds himself inside the world of his favorite game, Brave Hearts, after a night of gaming...Mistaken for “Raye Alvah,” the ruffian second son of a duke, he faces hostility from strangers and is publicly disowned by the noble family!And as he pieces together his strange new reality, he realizes he’s living as a minor villain destined to be forgotten after being defeated by the protagonist!And now...“Fuck this shit, why did it happen to me?”He must adapt to survive in this world.

In the foreign world, the martial artists dominate the world and the sword of the emperor controls the fate of hundreds of millions of lives! Long Yu, the number one killer on Earth, after dying, takes rebirth in this new world in an aristocratic family of martial artists but faces rejection because he is unable to practice martial arts.

- Description from Novelupdates

To be exact, the female lead is an “older sister” type, amid many beauties and handsome guys, she's no white lotus.Also, it's said that the name of this book is the same as a brand of sheep's milk powder.

In the past, the giants of the heavens and the gods were destroyed after the reincarnation of the world! Cruel curse, eternal hatred, Tan Yun is determined to never sink again! For the sake of loved ones and relatives, from now on, step on the corpse of the enemy step by step to surpass the peak! Defying the sky, killing all worlds, I am the only one!

- Description from novelbuddy