Shirakiin Ririchiyo’s dream of independence had long seemed impossible, and she felt doomed to the life of a secluded shut-in. Until, that is, she arrived at the mysterious mansion known as Ayakashi Kan, where every potential resident must pass a strict series of tests before being allowed in. The drawback to this private Eden, however, is that every resident must also have a personal Secret Service agent accompanying them at all times, and the agent assigned to her, Soushi Miketsukami, may be far more than he appears to be. Could the “guardian angel” looking over her shoulder be more than just foxy looking and actually a fox spirit? Get ready for supernatural sleuthing and spirited suspense as the most secretive secret service of all unleashes a whole series of stunning surprises in INU X BOKU SECRET SERVICE!
Maison de Ayakashi is an exclusive apartment complex; each tenant gets their own bodyguard. Ririchiyo has finally convinced her parents to let her live alone, but when Soushi introduces himself as her bodyguard, she will try everything in her power to drive him off.
Ririchiyo is out shopping with Sorinozuka, whose goal is to keep her out the complex until 6. When they return, Karuta has suddenly gone missing...
After dealing with making a good first impression at school, Ririchiyo notices Soushi turning a girl down. After asking him about it, her emotions get the best of her.
Watanuki has returned from training with his SS, Natsume. Watanuki, Natsume, and Souishi have known each other since childhood, and Natsume hints that he knows about Soushi's past.
Ririchiyo has been getting strange text messages from an unknown number. Though she shrugs them off, the messages are starting to become more frequent...and threatening.
Roromiya spends a lot of time in her own world, oblivious to everything else. Watanuki believes people just don't get her. Ririchiyo, meanwhile, wants to get closer to her but isn't sure how.
A ghost has invaded the mansion, activating its security system. Nobara, Sorinozuka, and Chino are locked in the cafeteria, Watanuki and Natsume in the hallway, while Ririchiyo and Miketsukami are locked in her room. This is the perfect time for Ririchiyo to express her feelings...but will she?
Ririchiyo wants the type of friendship the others share with their SS. But her inability to speak her true feelings doesn’t help. What can she do to break the barrier of Master / Servant between them?
A series of commands have appeared in the mansion. But that means nothing to Ririchiyo as she frets over her upcoming tea date with Miketsukami.
Tea time has gone sour with Kageru's sudden arrival surprising both Ririchiyo and Miketsukami. Kageru has come to pick her up to give her an important message.
Miketsukami's history has been exposed. A Child born with youaki blood is a reason for celebration, but in his family, things are very different.
The residents are burying a time capsule for their future selves. Ririchiyo has accidentally put the wrong letter inside the capsule and given a very personal one to Miketsukami.