Inu × Boku SS

Inu × Boku SS (妖狐×僕SS, Inu Boku Shīkuretto Sābisu, lit. The Dog and Me Secret Service), also known as Youko × Boku, is a Japanese manga series written and illustrated by Cocoa Fujiwara. An anime adaptation by David Production aired in Japan between January and March 2012. The anime has been licensed by Sentai Filmworks for streaming, and home video release in North America.

Part One "Prologue"
Volumes 1 to 4.

Known on the outside as merely a daughter of a rich aristocratic family, 15-year-old Ririchiyo Shirakiin is far from normal – she is an Atavist, a human with demon or yōkai ancestors with the ability to channel their supernatural powers. Wrought with insecurities about her birth and family, Ririchiyo protects her inner, most sensitive self through a sharp tongue, eventually leaving to move into the Maison de Ayakashi (メゾン・ド・章樫, Mezon do Ayakashi), better known as Ayakashi Hall or Ayakashikan (妖館), a high-security apartment complex where fellow Atavists reside. As Atavists are neither fully human nor supernatural, they tend to attract fully-grown, often dangerous demons, and so group together, each resident guarded by their own Secret Service (SS) bodyguard. Despite not requesting for a bodyguard, she finds herself served by Sōshi Miketsukami, the descendant of a nine-tailed fox who devotes his life to her. Although initially unwilling to accept him as her bodyguard, the two grow close and Miketsukami helps Ririchiyo suppress her bad habit as well as establish valuable connections with the residents at Ayakashi Hall; Ririchiyo also inevitably helps him become more emotional and to be more perceptive of the world, which he had not acquired due to his house arrest and isolation. The two eventually fall in love and begin a relationship. Instead of fulfilling her initial goal to be alone, Ririchiyo realises that she has instead surrounded herself with supportive friends. As a bonding activity, the residents decide to build a time capsule together for their future selves.

Unfortunately, this sudden peace is interrupted when Karuta Roromiya, Kagerō Shoukiin's SS, is attacked and heavily wounded by a fellow Atavist named Mikoto Inugami. Inugami declares his intention to recruit members for the Night Parade of One Hundred Demons, an army of Atavists that have lost their human sanity and become senseless yōkai subject to his command. Despite attempts to save Karuta, she eventually loses herself and becomes a part of the army, attacking her friends. Miketsukami is killed by Inugami in front of Ririchiyo while trying to protect her.

Part Two "If"
Volumes 5 to 8.

Nearly every one of the residents of Ayakashi Hall is revealed to have been killed as a result of the incident, except for Renshō Sorinozuka. 23 years have passed since then, and the deceased have reincarnated thanks to their yōkai blood. 15-year-old Ririchiyo, wrought with insecurities about her sharp tongue, leaves her home and moves into the apartment complex hoping to be alone, only to meet Miketsukami who employs himself as her SS. Unlike other residents, Ririchiyo has no recollection of her past due to her previous incarnation's trauma over Miketsukami's death, but slowly starts to remember after encounters with the others. Ririchiyo deduces that the Miketsukami now actually has no memories as well, and is merely acting out of an ingrained emotion, choosing to break off their contract and relationship as she confirms that she loved him in her previous life, not her current life. Years of calm is once again interrupted by news about the Night Parade, signalling that it has become an unstoppable cycle. As everyone works to stop it, Banri Watanuki, who has reincarnated as a middle-schooler, befriends Inugami, not realising who he is. The residents eventually discover that Inugami is constantly revisiting a time from 23 years ago using a special sacred tree, known as the Millenium Cherry Blossom Tree, and decide to send a time capsule containing letters for their past selves.

"Interlude"
Volumes 8 and 9.

5 short stories, each focusing on one or more of the main characters. Set sometime during Part 1.

Part Three "Awaken in Spring"
Volumes 9 to 11.

The setting jumps back to 23 years ago, in the first timeline, where the group are about to bury the time capsule containing letters to their future reincarnations as a bonding activity. As they dig a hole for the box, they find another box in its place containing letters from their future selves to them, warning them about Inugami's plans. With this timeline now deviating from its original course, Ririchiyo and Miketsukami have yet to cement their relationship, and she instead chooses to keep her distance from him after learning that he will die protecting her. The group manages to prevent the attack on Karuta, but are forced to return to their own homes, knowing that Ayakashi Hall is no longer safe. Back in his loveless home, Miketsukami is held in captivity again until Ririchiyo arrives to save him. The two finally reconnect and begin a relationship.

Reuniting, the residents learn that Inugami is acquainted with Shimon Satorigahara, an elderly Atavist who is revered as the leader of the Atavist community for her power to perceive the thoughts and memories of others by touching them. Because simply going out could mean an overload of information and subsequent death for her, Shimon was locked up at home since a young age, having to live vicariously through Inugami. As children, they had grown close, with Shimon trusting him enough to show him the Satorigahara family's Millenium Cherry Blossom Tree, a yōkai known as Sennenzakura that governs time. An accident however, caused Inugami to become immortal, and from then on his existence began to revolve around hunting and gifting Shimon the corpses of all Atavists, for her to read their stories and memories for enjoyment eternally. In the final battle, Kagerō manages to gather Atavists from all over the country to fight Inugami's army and a final showdown is held in the Satorigahara residence. Inugami is deterred by Watanuki's presence, whom he unconsciously considered as a friend, and killed by Miketsukami, ending the Night Parade and lifting his curse, causing all senseless yōkai to return to their Atavist form. As Shimon reads a dying Inugami's memories, she realises that he had loved her all along, amidst her hundreds of reincarnations. In an aftermath, the residents and their SS bodyguards continue towards a new life together, with everyone alive and well. Zange Natsume, who can See snippets of the future, pictures a scene where those from the "If" world are living happily together in a different timeline.