Moomintroll (Mumintrollet) - a spirited troll teen with a keen sense of adventure and fun and a generous spirit. Moomin lives life fully, and views the world with a feeling of wonderment for such simple pleasures as collecting stones and shells. As gullible as he is enthusiastic, he is also naive and extremely good-natured.

He is Snufkin's best friend, and often feels sad when Snufkin leaves the Moomin Valley during the winter. He has a crush on the Snorkmaiden and although the two sometimes are called, or call themselves a couple, he expresses his emotions to her discreetly, and their crush seems to be kind of a secret.