Hogwarts - Era of Darkness - Chapter 39 – Chamber of Secrets

Regaining the memories of his previous life, Cyril realised that he was an otome game’s character, the villainous daughter– Sophia’s butler.At the rate things were going, Sophia would eventually have the prince stolen away from her by the heroine, fall into darkness, and be executed.Wanting to save the villainous daughter he was so fond of, Cyril moved to eliminate all the factors that would cause her to fall into darkness, raising her up to be a talented and beautiful girl who could win the prince’s love, however…

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

I became the childhood friend of the protagonist in a novel. The childhood friend who died from taking drugs.

Feng Lingxi was the traditional family’s head mistress – a person with a charismatic yet sly personality with the ability to attract people easily to her side, and having the potential to take someone’s soul away. Crossing across boundaries from a decade ago to now, a world that gives woman full respect and acknowledgement….

Don’t be fooled by her, because she was someone who would act obediently in front of a crowd but, stabs them in the back when necessary! Disguising as someone that would gain her trust and belief! That was why the Emperor of Xian started doting on her, allowing her to become absurdly daring to do whatever she liked. This made the Empress speechless to tears.
That would be the cause of the kingdom’s downfall in the near future…

- Description from Novelupdates