Sora Kashiwagi, a high school student, is used to getting strange gifts from his father, who is on an excursion throughout the world. Unfortunately, these presents have turned out to be nothing more than nightmares. As a result, when his father sends him a massive parcel from Egypt, Sora expects the worst, only to be met with Mii-kun—a charming, pint-sized mummy! While Sora is first skeptical, he eventually realizes that Mii-kun is a gentle creature hungry for attention. Throughout their funny daily lives, the odd duo meets other individuals with unusual pets while also building their friendship. Although caring for a pet is a demanding responsibility, Sora is determined to care after the adorable Mii-kun.