After being kicked out of home, a man dies trying to protect some kids from being hit by a truck, as usual, he wakes up in a new world.
As soon as he opens his eyes, a huge man begins to kiss him, he is a bit annoyed, but after that, a gorgeous woman begins to talk to him in a strange language and offers him a hug.
Our hero, Rudeus, tries to hug her and realizes that his hands are small, and his body is as fragile as a baby. Somehow, he has his previous memories, and lust, and it is not rare to see him stare at her new mother and maid in a strange way.
As the months pass, and he grows up, he begins to find his new life boring and decides to do something with his spare time, trying to learn as fast as possible.
He understands that his new father, Paul, seems to be a warrior, and his mother, Zenith, some sort of magician.
A light novel series by Rifujin na Magonote, serialized online on Shousetsuka ni Narou in November 2012, then printed by Media Factory. A manga adaptation by Yuka Fujikawa began serialization in 2014. An anime series adaptation by Studio Bind premiered in January 11, 2021.