About

You are an ordinary person living in a world where your social standing is determined by your pet! And guest666 has become your pet!!! Pets have ranks, and the lower the rank, the lower your social caste. For now, the setting is high school. By the way, the pet ranks are: S-Rank: The strongest. High caste, practically gods of this world. Only a few hundred exist globally. A-Rank: Strong and rare. Not as good as S-Rank, but still uncommon. B-Rank: Slightly rare. You see them every now and then. C-Rank: Average. D-Rank: Weak. Owning one makes you an outcast. F-Rank: The weakest. Mocked by everyone and intensely hated. However, even an F-Rank can be raised slightly through training. Reaching S-Rank through this method is nearly impossible. For some reason, no matter how much you train guest666, he stays F-Rank and never improves.