TV-Series
Description
Ryoma Takebayashi, a 39-year-old Japanese man, endured a harsh life marked by paternal abuse. His father enforced brutal martial arts training, striking him with a baseball bat for imperfection and inflicting severe internal injuries after a school bullying incident. Financial neglect by his father contributed to his mother's death from overwork. Ryoma faced further misfortune through false accusations of excessive self-defense during an armed robbery, leading to social ostracization and exploitative employment with workplace abuse. His life ended anticlimactically with a fatal brain hemorrhage triggered by a sneeze.

Post-death, deities Gain, Kufo, and Lulutia revealed his suffering resulted from manipulations by Earth's God, who orchestrated trials to corrupt him into becoming a serial killer. The three gods reincarnated him into the fantasy world of Seilfall as an eight-year-old boy, altering his appearance to seem gentler than his former intimidating physique. He retained all memories and skills from his past life, including martial arts proficiency, meditation, and knowledge of modern chemistry and engineering.

Initially, Ryoma lived in isolation for three years within the Forest of Gana, focusing on survival, magic practice, and slime research. During this period, he discovered evolutionary traits in slimes by altering their diets and environments, creating variants like Sticky Slimes, Medicine Slimes, and Scavenger Slimes. He also eliminated local threats, including goblins and a bear.

At age eleven, he encountered Duke Reinhart Jamil and his family, aiding their poisoned guards. This meeting facilitated his integration into Gimul society, where he registered with both the Adventurer and Tamer Guilds. His innovations included using slimes for cleaning latrines and homes, leading to the founding of the Bamboo Forest Laundry Shop. As an employer, he implemented modern labor practices—weekly holidays, health insurance via healing slimes, and fair wages—which contrasted sharply with local norms and reflected his traumatic past. His business later expanded to Lenaf, aided by employees like the Norad twins and former researchers Tony, Lobelia, and Caulkin.

Emotionally, Ryoma experienced regression due to his child body, resulting in heightened expressiveness and occasional impulsivity despite his adult memories. He formed familial bonds with the Jamil family, particularly Eliaria Jamil, whom he taught magic control and slime taming. He maintained divine connections, learning from gods like Serelipta about Earth God's interventions, including a latent "Curse of Isolation" from a cursed magic stone. His combat style blended martial pragmatism—using poison slimes against bandits—with overwhelming magical prowess across all elements, though he concealed his full capabilities to avoid exploitation.

Key developments included claiming an inheritance from deceased adventurers whose identities facilitated his backstory, participating in guild initiatives like treant wood harvesting, and countering rumors targeting his business. He continued advancing slime research, discovering species like Nightmare Limour Birds and refining alchemy through rust conversion into pure iron. Ongoing challenges involved managing emotional volatility during confrontations and navigating societal expectations while upholding his ethical standards.