Death March kara Hajimaru Isekai Kyusoukyoku (WN) - Side Story: Sisters

Riding out the apocalypse on a tropical island isn't exactly a vacation. When mana arrives on Earth, Coop finds himself isolated in paradise with only one real option to survive. He needs to claim a civilization shard and level up. Coop maximizes his chances by carefully selecting a class and committing to progression. He’ll need to grind thousands of monsters to compete on the system's leaderboards while upgrading his settlement to represent the factionless.

At 79, Adom is an old mage who has known nothing but illness and regret. When the world finally burns and all hope turns to ash, at the last beat of his fading heart, a mysterious being appears in the dimming light with a simple question:“If you could try again, would you?”What's left to lose when you've already lost everything?A handshake seals the deal, and Adom wakes up on his old school grounds, sixty-seven years in the past. When everything is still possible. A second chance with all his knowledge intact, his memories preserved, and his youth restored.This time, Adom wants it all: to feast on food he's never had, to travel a world still full of wonder, to finally live the life he dreamed of. There's just, as always, one small catch—he needs to prevent the end of the world first.But as Adom will soon discover, changing history might demand sacrifices even greater than watching it burn...

She is the slow-witted idiot of the Prime Minister’s Residence. Everyone bullies her. He is the most respected and unfeeling Prince, with frightening ability and absolute envy! Together, they are conferred an imperial edict of marriage.

She acts stupid and tries to decline in every way possible while he despotically escorts her into the wedding…… everyone ridicules the match, but no one knows that the “idiot” has transformed from a loser into a talent.

After the marriage, when they encounter the Empress Dowager examining the room, they act in concert with each other and pretend to be two mandarin ducks deeply in love. Afterwards, she laughs, “The performance has ended. Your highness, please return.”

He laughs softly, “Since you’ve got onto this Prince’s bed, don’t even think of getting off.”

- Description from Novelupdates

From [Running], to the physics-defying [Godspeed].From [Aiming], to the causality-transcending [Bullseye].From [Health Cultivation], to the everlasting [Immortality] among men.From [Fitness], to the flesh-ascending [Turning into a Dragon].Having been reborn, Xue Jing, after gaining a panel that infinitely enhances skills, set a minor goal for himself.In this dangerous world filled with martial artists, Blessed Ones, and Transformed People, he aimed to rise above all merely with his mortal flesh and blood—to become the supreme deity among men.