After thirty years of service as the kingdom's hero, Alec is abruptly dismissed by the king and replaced by the younger, charismatic Marius. Having been raised as a hero since the age of nine, Alec possesses no practical life skills and is utterly unprepared for the outside world. Betrayed and humiliated by Marius, who reveals his true contemptuous nature, Alec is left with a severance of one hundred gold coins and no idea how to survive.

Desperate and lacking even basic knowledge of prices or trustworthy people, Alec decides on an unusual solution: he will purchase a slave who can supply the common sense he lacks. He heads to a slave market, where he encounters Lyrishia, a serene and beautiful woman dressed as a sister. Despite her status, Lyrishia is kindhearted and intelligent, and Alec buys her. He soon learns that Lyrishia is actually a fallen angel, a fact that only deepens their bond.

With Lyrishia by his side, Alec begins a new life as an adventurer, enjoying the freedom and affection he was denied as a hero. However, his newfound happiness brings a new goal: because Lyrishia is a long-lived angel, Alec wants to obtain a rejuvenation potion so he can grow old together with her. The potion costs two hundred and fifty million gote, a staggering sum. To raise the money, Alec takes on dungeon exploration and odd jobs, including a dangerous mission to rescue mistreated slaves. Meanwhile, the kingdom that ousted him struggles under its new hero team, which fails at even simple monster subjugation.

The story follows Alec's second life as he balances love, adventure, and the pursuit of a future with his beloved angel, all while navigating a world he barely understands.