Muushika is a young female polar bear inhabiting the Arctic. She lives with her family, including her father Mu, the wise leader of the Great Northern animal kingdom, and her companion Mishka, a more daring polar bear cub. Muushika herself possesses a thoughtful and introspective nature. Her background involves exploring the Arctic environment, leading to adventures where her curiosity manifests, such as inadvertently discovering swan eggs and disrupting a bird village.

She demonstrates notable intelligence and perceptiveness, observing her surroundings with keen awareness. This curiosity fuels her desire to learn about the world beyond her home. Her personality blends loyalty and compassion, particularly evident in her protective stance toward family and friends. She shares a significant bond with Mishka, and their adventures include encounters with characters like Aura, a playful seal. Later, the duo is joined by Mashka, a bear girl who lost her mother, forming a trio.

A pivotal moment occurs when human hunters injure her father, Mu. This forces Muushika to assume responsibilities tied to his role, safeguarding the animal community during their annual Summer Festival and confronting the hunter threat. Throughout this challenge, she displays resourcefulness and problem-solving abilities, channeling her thoughtful nature into practical actions to protect others. Her development underscores an increased sense of duty and resilience, shifting from exploratory adventures to undertaking critical tasks for her community's welfare.