After dying in his mid-twenties while saving a child from a traffic accident, a Japanese man is reincarnated into a harsh fantasy world. A mysterious god known only as Indeed-Missy grants him a second chance at life as a young boy named Thor, but his sole magical ability allows him to cook monsters. Before he can even reach his fifth birthday, his neglectful parents attempt to sell him into slavery, and after their subsequent deaths, he finds himself a penniless orphan forced to survive by any means necessary. Taking refuge in the sewers beneath a city, he uses his culinary magic to process poisonous creatures from the dungeon into edible, if unappetizing, meals.

His solitary struggle for survival takes an unexpected turn when he discovers two young beastfolk girls on the verge of death. Both are four years old and have escaped from captivity or enslavement. Despite knowing that taking in extra mouths to feed could spell his own ruin, Thor finds he cannot walk away, driven partly by the memory of his past life fondness for animal ears. He names the two girls Shiro and Kuro, and they begin living together as an unconventional family in the sewer tunnels. Shiro and Kuro quickly prove to be powerful in their own right, learning offensive magic from Thor and fighting low-level dungeon monsters to help gather ingredients. The trio adopt a simple but harsh routine of dungeon crawling, fighting, and cooking, all while wearing mismatched outfits that include butler and maid uniforms.

The story follows their day-to-day existence as they grow slightly older, turning from four to five years of age over the course of the first major narrative arc. Thor uses his storage magic to preserve ingredients for years at a time, and he insists that his combat spells, like Water Needle, are actually intended for food preparation. The dungeon environment remains largely unexplained, and Thor shows little curiosity about the broader world, instead focusing entirely on the immediate challenges of survival and caring for the two beastfolk children. Their adventure is a cycle of fighting poisonous monsters, cooking them into stew, and leveling up their abilities, with Thor’s goal being the protection and raising of his furry-eared companions.

Written by Yuu Tanaka, known for A Late-Start Tamers Laid-Back Life, and illustrated by LLO, the series was originally released in Japan in July 2024. The English edition is published by J-Novel Club.