The Attack of the Wastrel - Chapter 138 - I’m Going to Make a Confession

Lee Se-Hoon, the blacksmith of humanity’s last desperate united force, fought against the demons until the very end. However, the result was mutual destruction, with the world coming to an end. The moment he took his own life over that futile conclusion—

“…What is this?”

He had regressed to his days as a candidate at the hero training institution, Babel Academy. Having obtained a second chance, he swore to use anything as material to gain victory this time. Anything at all!

Waking up again in his seventh reincarnation, prince Jing Beiyuan found himself back in time, when everything had yet to be set in motion. Having been given a second chance, Beiyuan had to survive court and decide whether it was finally time for him to let go of his feelings; all while trying to handle the youthful, innocent force of nature who had suddenly barged into his already complicated life.

- Description from Novelupdates

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

After experiencing heartbreak from being abandoned, he enlisted in the military.

And then, he became a war hero.