MTL - Mecha and Knife - Chapter 803 whack the gopher first

Yeon-woo had a twin brother who disappeared five years ago. One day, a pocket watch left by his brother returned to his possession. Inside, he found a hidden diary in which was recorded “By the time you hear this, I guess I will be already dead….”

When a person dies, they either die light as a feather (aka unimportant) or heavy as Mt. Tai (aka very important).

Rocco Di Malvento lived a short, but loving life in his previous world, surrounded by a caring family. Despite suffering from a terminal illness, he found solace in books, especially his favorite BL novel >. But when he dies, he wakes up in an unexpected new life—as the weak, neglected second son of a powerful mafia family.Now reborn in the world of the novel, Rocco finds himself in a terrifying situation: he's the useless younger brother of Sylas, the main protagonist, and likely doomed to die young unless he changes the course of his life. So, what's his plan? Simple—befriend the protagonist, avoid being a spoiled brat, and secretly recruit Sylas's future allies to protect him.First target? Georgio the Hyena, an infamous killer. Rocco's strategy: charm the terrifying man and make him his ally instead of Sylas’s.It's a ridiculous plan, but hey, at least Rocco is trying. Can he survive the mafia world and avoid his tragic fate? He hopes so. After all, he’s just a kid trying to make the most of his second chance!

MC (female protagonist) dies in a plane crash and wakes up in the body of a beautiful but corrupt and lascivious prime minister in ancient times, Zhang Qinglian. As circumstances decree, he (she) cannot reveal that the original owner’s soul is gone else calamity might occur. So he (she) decides to walk a righteous path, determined to help the lovely but simple little emperor rule the country. Not backing down after facing torture, not losing courage, destroying rebellions and facing off with scheming princes.

- Description from Novelupdates