"Inu X Boku Secret Service" is a supernatural comedy-drama anime set in the exclusive Ayakashi Kan, a high-security apartment complex reserved for individuals with unique backgrounds and abilities. The story centers on Ririchiyo Shirakiin, a sheltered and emotionally reserved young woman from a wealthy family, who moves into the complex to gain independence. Upon her arrival, she is assigned a Secret Service agent, Soushi Miketsukami, who pledges unwavering loyalty and refers to her as his "master." Soushi, a fox-like ayakashi with a calm and polite demeanor, becomes Ririchiyo's constant companion, often blurring the lines between servant and protector.

The narrative explores the dynamics between Ririchiyo and Soushi as they navigate their evolving relationship. Ririchiyo struggles with her inability to express her emotions and her tendency to push people away, while Soushi's devotion and mysterious past gradually break down her defenses. The series delves into themes of trust, self-discovery, and the complexities of human connection, often balancing lighthearted moments with darker undertones.

The supporting cast includes other residents of Ayakashi Kan, each with their own distinct personalities and supernatural traits. Characters like the cheerful and mischievous Kagerou Shoukiin, the stoic Nobara Yukinokouji, and the enigmatic Karuta Roromiya contribute to the apartment's vibrant and eccentric atmosphere. Their interactions with Ririchiyo and Soushi add depth to the story, revealing the residents' shared struggles and the bonds they form despite their differences.

As the series progresses, it uncovers the hidden layers of Soushi's past and his connection to Ririchiyo, intertwining their fates in unexpected ways. The narrative also touches on the broader implications of the ayakashi world, blending supernatural elements with emotional storytelling. The balance between humor, romance, and drama creates a multifaceted narrative that appeals to a wide audience, offering both entertainment and emotional resonance.