Past Life Returner - Side Story 15: The Next Day - Kwon Seong-Il

After assisting the man she loves with all her heart to the throne, Li Wanrou dies miserably in the cold palace, her dead body wrapped in a broken mat and thrown into the disorderly funeral hillock.

After a god screws up and accidentally takes high schooler Shou’s life, he offers him reincarnation with a gift to make up for it. Shou asks to retain all his old memories for the new life. Shou is reborn as Will, a noble’s son in a world where magic use is common and involves knowledge of kanji characters. With all his memories, he’s a brilliant toddler, and when he experiments with magic, he finds that he has an amazing talent for it! What’s more, though he was smart but unloved in his old life, in his new life he has a mother and a father who both love him deeply. His future as Will is looking very bright and cool!

Have you ever thought that the state of the world as it presently is, could revert to the laws of the ancients? When a series of strange incidents beginning with the disappearance of his friend led Luo Yuan to question the possibility of an apocalypse, he becomes embroiled in the midst of a global-scale chaos.

Evolution has turned the flora and fauna of the vast and bountiful Earth into something that had never been seen before. Coincidentally, the all-dominating Homo sapiens have ended up at the bottom of the food chain. From mystery to crisis, will Luo Yuan discover a means of saving humanity by racing to the top of the food chain? Or will he strive in accordance with the law of the jungle? It is the dawn of an age of the survival of the fittest.

- Description from Novelupdates

A magical 'Universal Toolbox' led Joe Ga into the arms industry.The complex and unpredictable nature of the world caused Joe Ga to gradually change his goals...“Sir, how did you end up here?”“I don't know, I just wanted to make some money at first, buy a house, marry a wife. But slowly, as more and more people appeared around me, my goals started to change.”“So what are your goals now?”“Now, I just want to retire peacefully with my guys, really!”