"Ketsu-Inu" is a manga series that blends elements of supernatural horror, psychological tension, and dark fantasy. The narrative centers on a young man named Haruto, who becomes entangled in a series of bizarre and terrifying events after encountering a mysterious stray dog with an otherworldly presence. This dog, which appears to be both a harbinger of doom and a protector, forms a strange bond with Haruto, altering the course of his life in ways he cannot fully comprehend.

The story unfolds in a small, rural town plagued by a series of gruesome murders and unexplained phenomena. Haruto, initially a passive and somewhat aimless individual, is thrust into the role of an unwilling investigator as he begins to uncover the dark secrets of his town. The dog, which he names Ketsu, exhibits supernatural abilities, including the power to manipulate shadows and sense malevolent entities. As Haruto delves deeper into the mysteries surrounding Ketsu and the town, he discovers that the dog is connected to an ancient curse tied to his own family lineage.

The curse, rooted in a tragic event from centuries past, involves a pact made with a malevolent spirit that demands bloodshed to maintain balance. Haruto’s ancestors were once guardians tasked with containing the spirit, but their failure led to the curse manifesting in the present day. Ketsu, it is revealed, is a manifestation of this spirit, bound to protect Haruto while simultaneously drawing him closer to the curse’s inevitable consequences.

Throughout the series, Haruto encounters a cast of characters who are either victims or perpetrators of the curse. These include Aya, a childhood friend with a hidden connection to the supernatural events, and Renji, a enigmatic figure who claims to have knowledge of the curse and its origins. As Haruto struggles to reconcile his growing bond with Ketsu and the horrifying truths he uncovers, he is forced to confront his own fears and the moral ambiguities of his actions.

The plot is driven by a series of escalating confrontations with malevolent entities and the gradual unraveling of the curse’s history. Themes of guilt, sacrifice, and the cyclical nature of violence are explored as Haruto grapples with his role in breaking the curse or perpetuating it. The narrative maintains a tense, foreboding atmosphere, with moments of visceral horror balanced by introspective character development.

By the series’ conclusion, Haruto must make a pivotal choice that will determine not only his fate but also the future of the town and those connected to the curse. The resolution is both poignant and unsettling, leaving lingering questions about the nature of the curse and the true extent of Ketsu’s influence. "Ketsu-Inu" is a compelling exploration of supernatural horror intertwined with personal and familial struggles, offering a narrative that is both gripping and thought-provoking.