It’s Lonely To Be Invincible - Chapter 1158

In the vast and boundless continent Cangtu, there were ancient sects governing the Ten Old Domains, unworldly immortal clans beyond the Blue Sky, and primordial demon gods dominating the dark abyss that together created a great number of brilliant stories over the long course of the history.

Our straight (?) bottom woke up ten years into the future and found himself on the bed of his childhood friend… At the start, the bottom was shocked to his very bones, but he soon quickly accepted this premise and found the whole situation to be rather amusing. Precisely then, the bottom once again went back to his timeline — back to when he and the top were just platonic childhood friends.

Landmines include but are not limited to: Sweet & naive bottom, a president story, logic is dead, slow-progressing romance, the protagonist’s name has too many character strokes, the names are hard to pronounce, too many gay characters…

He Lang died by his own hands for the sake of his imperial younger brother’s ambition, whom he loved. He was offered to be reborn in exchange for giving up his past romantic feelings. Reborn without the burden of his romantic feelings, he brings with him a manual to new worlds. He wholeheartedly followed the instructions of the manual to complete the tasks, not knowing that the originally slag gong was blackening…
He pleaded to his affectionate Emperor brother to release him, he pleaded to the paranoid prisoner next door, but until the end he remained baffled.
In the end, he discovered that the full name of the manual was – “Slag Shou Cultivating Manual”
Σ (っ ° ° °;) っ!

- Description from Novelupdates

Lieutenant Jack Fritz is a self centered American man of German descent. He like many joined the United States Navy in hopes of getting an easy life and easy money. In fact getting money and taking it easy is all he has ever really wished for in life.However life seems to have other plans in-store for Jack as he suddenly finds himself at the beginning of World War 3. Though his fight does not last for long as he is suddenly blown to bits by a missile and sent into the afterlife, but instead of going to heaven Jack is dragged to another place where he is given another chance at life by some fiery demon for a price.Having been given no other chance Jack does as the demon says and earns himself life again. Though he doesn't return to his original world, but a medieval one. With no guidance and no higher purpose given to him he simply decides to do the best that he can within this new world of his. This time he will for sure earn that perfect life of his and possibly a lot more.But little does Jack know his fate is not his own and there are many sinister things in-store for him. Also the world he finds himself in is not a safe or simple medieval world, but one beset by dangers from all sides that are already little by little driving humanity towards its extinction.