While Others Cultivate, I Use My Unique RPG Leveling System to Cultivate Smut Romance With Their Girlfriends! - Chapter 13: Smitten (+18/light smut)

Humanity has been gradually transported to the Abyss by a bored god to compete against other races and monsters.The problem is… humanity failed. In a last desperate push the strongest survivors chose a comrade to travel as far as possible back in time.

One day, Luo Jian woke up from his sleep and found himself in a locked chamber where the door and window were all sealed. A note with a few lines written on it was tacked to the wall: “Escape from this room within an hour, otherwise, you will die.”

There is a sequel called Reincarnation Night (轮回之夜) that takes place in the same universe but has different main characters

- Description from Novelupdates

The former mercenary assassin Chen Tianlong has been asked to be the bodyguard and private doctor of Lin Wushuang, a pretty lady who is still a student. Their stories in the campus begin.“What's wrong, Tianlong?”“Your daughter is not sick, it's just that her Yin Qi is too heavy. The treatment for her is quite simple, find a man with abundant Yang Qi... and let him hold her while sleeping.”“This concerns Wushuang's life and death, and I definitely trust Tianlong, so let him try.”

He rose from hardship, but was felled by betrayal. From then on, one man, one gun; treads the path between Evernight and Daybreak to became a legend. No matter what was destined to be his fate, he intends to become the ruler who dictates.