Fukigen na Koushaku-sama wa Uso Hakkenki Tsuki Reijou no Torisetsu wo Goshomou desu不機嫌な公爵様はウソ発見器付き令嬢の取説をご所望です; The Grumpy Duke Desires an Instruction Manual for the Lie-Detector Lady; The Brooding Duke's Guide to the Lie-Detecting Lady

Countess Ophelia has the special ability to "see through lies." Because of this ability, she is unable to socialize and lives a reclusive life. One day, Ophelia attends an evening party to see Claudio, the duke she longs to meet, but she reacts to the aristocrat's "lies" and shivers and falls in the hall... Her brother takes her away, but Claudio, who is suspicious of her appearance, catches her eye...?