'Love Tripped Into My Room: I Just Wanted Peace, Not Panties' - Chapter 20: It’s School Camp. I’m Sharing a Cabin With All of Them. Send Help.

Humanity was on the brink of destruction. Muyoung, an assassin from the Forest of Death, fell to his knees. There were corpses all around him. For years, he had worked for the Forest of Death and had finally been able to eradicate them. Now, he, himself, was about to die. He closed his eyes as he felt his heart stop beating.

I woke up in my sleep, and a strange door appeared in my home…Behind every door is a strange world.

In the nightmare world, Jiang Cheng added the news from the strong man to the fat man, and he almost cried when he heard the latter, “If you die here, the whole family will stand upside down and bleed?”

“Is such that.”

“Then I don’t think you are too scared?” The fat man widened his eyes.

Jiang Cheng turned his head and said in a very formal tone: “Because I am an orphan.”

- Description from novelbuddy

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….”