MTL - America’s Big Hero - v2 Chapter 522 : battle battle

A calculating merchant of noble birth lives a comfortable life managing his guild's business at the Imperial Academy—until lightning strikes him, leaving him with prophetic visions of a disastrous future. In these visions, he's expelled from his family, branded a traitor who aids demons, and worst of all, becomes a penniless beggar. When the supposed “protagonist” of these prophecies enrolls at the academy, he realizes his countdown to ruin has begun. Now he must use his foresight to rewrite a story where he's cast as a third-rate villain, all while navigating ancient dungeons, demonic threats, and the troublesome “hero” who might be the key to changing his fate.#MoneyIsEverything

Three Days of Happiness is a novel by Sugaru Miaki, also known as Fafoo. It’s a rewritten version of the story originally posted to 2ch.

The premise of the story revolves around a shop where one can sell away the remaining years of their life, and the consequences of doing so.

“I Say A Little Prayer” is a short related story which was posted along with the novel’s release. It spoils some things about the main story, but nothing major.

When the night came, there was a twittering sound in his ears, and the monster in the shadow began to move restlessly. Jason’s hungry stomach began to roar, and he couldn’t help swallowing saliva. Hunger is the best spur.

When an era came to an end, various forces set foot in cultivation to compete for immortality. A young boy who spent most of the time sleeping got lucky in the troubled times and became an unparalleled immortal who could cover the sky with a snap of fingers. Was he going to live forever?

- Description from Novelupdates