A guy buys a kappa on impulse and discovers that owning a mythical creature is nothing like the instruction manual promised. The comedy lives in that gap between theory and reality, where every training technique backfires in ways no book could predict. What starts as a simple pet-owner premise becomes a quiet meditation on patience, failure, and learning to live with something that refuses to cooperate with your plans.
A young man impulsively purchases a kappa from a pet shop and names him Kaatan, launching himself into the unpredictable world of cryptid pet ownership. Armed with nothing but a guidebook on kappa care, he returns home determined to raise this mischievous creature into a well-behaved companion. The manual promises straightforward training methods and behavioral tips that sound foolproof in theory. Reality proves messier. Kaatan absorbs lessons one moment and completely forgets them the next, or simply refuses to cooperate altogether. The young man's patience gets tested constantly as his aquatic roommate prioritizes chaos over obedience. What begins as a straightforward project devolves into a comedy of errors, where each attempt at training backfires in unexpected ways. Yet our protagonist persists, determined to transform Kaatan from a troublemaking handful into something resembling a functioning household member. The series finds humor in the gap between pet-raising expectations and the stubborn, unpredictable reality of living with a supernatural being who has zero interest in following instructions. It's about patience meeting mischief, and whether love and determination can survive countless failed training sessions.