After playing the VRMMO World Fantasy Online with fanatical dedication for nearly a year, Yuna, a 15-year-old shut-in who is relatively affluent, receives a bear costume from the game's administrators. Although the outfit is somewhat embarrassing to wear, it possesses overpowered stats and effects that render her character significantly more powerful. Upon accepting the bear equipment, she is transported to another in-game world from which she cannot return to reality. Confused and unable to log out, Yuna begins exploring this new environment. She rescues a girl named Fina from wild wolves, and Fina subsequently guides her to the city of Crimonia. Due to her eccentric bear attire, Yuna stands out wherever she goes; combined with her enhanced fighting prowess, her reputation rises quickly, leading people to give her the nickname "Bloody Bear." Undeterred by this change in her life, Yuna decides to assume the role of an adventurer and fully enjoy herself in her new world.