After The Calamity - Chapter 9: I Felt It

Florentia was reincarnated as the illegitimate child of the richest family in the empire.

Sato Yu is a 12-year-old boy. He is a deprived person. His life is depriving. His step father has a large amount of debt.

Violet skies, a world undergoing massive changes, a deficient moon, interlinking voids…
When the world experienced a cataclysmic event,the majority of living things ceased to exist. Although humanity survived by hiding in the last safe zones, humans had to face mutated dire beasts and colossal source beasts that could break through the space barrier and enter the earth at any second.
Luo Yunyang, a young man who grew up in those calamitous times, obtained an attribute regulator and set out to walk the path of supremacy!

- Description from novelupdates

Lu Xiao had followed his master for eighteen years, excelling in both medicine and martial arts.After five years of military service, he returned to the city to search for his origins.Faced with flashes of knives and shadows of swords, he was decisive in killing, dominating everyone.When it came to the matters of the heart, he said, “Still… the Young Miss is the best.”