Rosine

When she was human, Rosine had pale skin, light blue eyes, and reddish-blonde hair reaching down her back, with a boyish streak to her. Her genuine apostle body is a huge female luna moth tinted aqua, and between the two lies a more human-looking released shape washed in green-blue. Poison sifts from the powder that coats her wings, while her long proboscis serves either as a spear for impaling or a thin edge for cutting. At full power she flies faster than sound, sacrificing precision for speed and dragging sonic booms fierce enough to knock a foe off balance even when the strike misses.

As a child she was daring and boyish, whiling away hours in the forest snaring little animals, yet her brightness was frequently a front pulled over deep sorrow. The abuse she endured at home curdled into a distorted idea of kindness: sure that hunger, cold, and war exist only to wound children, she remakes them as elves so nothing may ever wound them again. Naming herself queen of the elves, she grows intensely possessive of her friend Jill, forever embracing her and claiming her as her own, though her love for the girl seems real and protective. Facing Guts in combat, she even slips into flirtation.

Rosine came into the world after enemy soldiers assaulted her mother in wartime, which left her father unsure the child was his. Their endless quarreling pushed her out into the woods, where she gathered odd trinkets, among them a curious stone off a riverbank, and grew close to young Jill, sharing a private telling of the Peekaf tale and swearing she was an elf. She fled toward the Misty Valley, and once her parents tracked her down, her father beat both her and her mother; sickened by the sight, her beherit awoke and she gave up their lives, rising anew as an apostle in the shape of an elf. From there she abducted children to remake as elves and warped stray men into guardians, while her pseudo-apostles began preying on the villages nearby. The night before the Eclipse she rode with the apostles who massacred the wounded Band of the Falcon, seen only for an instant by Rickert.

In the Conviction Arc she came up against Guts after he set fire to a cluster of her familiars, dosed him with poison, and escaped carrying Jill, urging the girl to turn into an elf and dangling a haven free of human warfare. When Guts torched her emergence cave, Rosine was driven into her real shape for a long, frantic duel. He landed the killing stroke at last by using her devotion to Jill against her, and as she changed back, one arm severed, she quietly pleaded for her parents' pardon and confessed she had never really put stock in elves. Puck softened her death by assuring her his own kind had once dwelt in the valley. Lost to delusion, she rose into the air a final time meaning to return to her parents, only to crash to her death while recalling brighter days with them. The Skull Knight came later to her scorched tree and took away her beherit.