The protagonist, originally an overworked office worker from 23rd-century modern society who died from overtime. She was an orphan who lived 35 years without knowing her biological parents. After arriving in the Underworld, she spent 300 years preparing for exams. She passed the Quick Transmigration Department exams but missed the internship slot, then got accepted into the newly established System Department as an intern employee. She was assigned System 009 and transmigrated into a mission world set in 1960s China, becoming the youngest daughter of the third branch of the Lu family in Hong'an Brigade at age five. Her mission objective is to be the protagonist of her own life and live out her natural lifespan.
