Rosine is a female apostle who sacrificed her parents to transform into a female elf with the wings and antennae of a luna moth. She also has a small pair of moth-like limbs near her hips and a 'helmet' resembling the head of a luna moth. Her motivation stems from the legend of Peekaf, a child who believed he was an elf and lost his human parents as a result. Rosine calls herself the Queen of the Elves, and her true form is that of a monstrous female luna moth.
Living in the Misty Valley, she terrorized a nearby village by sending insect demons disguised as elves to eat livestock and people, as well as capturing children to turn them into more insect demons using cocoons. Guts, Puck, and Rosine's former friend Jill ventured to the Misty Valley to confront her. Rosine offered to make Jill an elf apostle, tempting her with the promise of flight, but Jill was uneasy with the violent nature of the elf demons.
Guts discovered and destroyed the cocoons, enraging Rosine, who then fought Guts until she was too injured to continue. As Guts prepared to deliver the final blow, Jill shielded Rosine with her body. Although this did not stop Guts, Jill's father arrived and shot Guts with an arrow before he could act. Guts was subsequently attacked by the Holy Iron Chain Knights, led by Farnese.
Mortally wounded, Rosine finally understood the moral of Peekaf's story and, in her delirium, attempted to return home to her parents but ultimately succumbed to her injuries and fell from the sky to her death. In some translations, she is referred to as Roshinu. Rosine makes a cameo appearance in the 22nd episode of the anime, where Rickert spots her hovering over a lake before the camp is attacked by other apostles. She is seen standing apart from the horde as they devour the wounded Hawks.
