Tsunejiro, a fox ninja trainee of the Nenga school, studies the art of assassination under a bear sensei alongside fellow foxes and raccoons. His quiet timidity sets him apart from his brash peers as he navigates a shadowy world of rivalries: the simian Koga clan and canine Iga warriors clash in ancient feuds, while the Dobe—a renegade faction of former Nenga students—threaten the school’s legacy. Tensions escalate when a penguin recruit joins their ranks, upending group dynamics and fracturing established expectations through interactions marked by skepticism and disillusionment. Though his mother is hinted at through occasional references, their relationship remains undefined, leaving his familial ties shrouded in mystery.