The viscount's daughter, Chloe, was the chief magical tools artisan for a country that perished a thousand years ago in her previous life. On the country's orders, she had created many weapons of slaughter. She laments her previous life and decides to, "live a respectable life this time." One day, at her graduation party, her best friend's engagement is broken off because of a lie. Chloe tries to save her best friend by unraveling the truth. 前世の罪を償うため、婚約破棄騒動の真実を解き明かして命の危機――!? 前世で殺戮の魔道具を作っていた子爵令嬢クロエ。 千年後の平和な世に転生した彼女は前世を悔やみ「今世ではまっとうに生きよう」と決心する。 親友が嘘の罪で婚約破棄されてしまい、クロエは真実を解き明かすが…!?