The main character, Lucas, was born into a family of heroes living in the demon realm and received a Spartan education from an early age. Thanks to her, she has gained super strength, but perhaps because the people around her were so amazing, even after she left her parents, she still doesn't realize her own abilities. After being used as an irregular porter for a small party of adventurers for two years, Lucas is banished and decides to live as a solo adventurer while keeping the insane strength that is instilled in the hero family.