Then one afternoon the butterfly wobbled out of a breeze and lit on the tip of her horn. He was velvet all over, dark and dusty, with golden spots on his wings, and he was as thin as a flower petal. Dancing along her horn, he saluted her with his curling feelers. “I am a roving gambler. How do you do?”
The unicorn laughed for the first time in her travels. “Butterfly, what are you doing out on such a windy day?” she asked him. “You’ll take cold and die long before your time.”
"Death takes what man would keep," said the butterfly, "and leaves what man would lose. Blow, wind, and crack your cheeks. I warm my hands before the fire of life and get four-way relief." He glimmered like a scrap of owl-light on her horn.
"Do you know what I am, butterfly?" the unicorn asked hopefully, and he replied, "Excellent well, you’re a fishmonger. You’re my everything; you are my sunshine; you are old and grey and full of sleep; you’re my pickle-face, consumptive Mary Jane." He paused, fluttering his wings against the wind, and added conversationally, "Your name is a golden bell hung in my heart. I would break my body to pieces to call you once by your name."
"Say my name, then," the unicorn begged him. "If you know my name, tell it to me."
"Rumpelstiltskin!" the butterfly answered happily. "Gotcha! You don’t get no medal." He jigged and twinkled on her horn, singing, "Won’t you come home, Bill Bailey, won’t you come home, where once he could not go. Buckle down, Winsocki, go and catch a falling star. Clay lies still, but blood’s a rover, so I should be called kill-devil all the parish over." His eyes were gleaming scarlet in the glow of the unicorn’s horn.
She sighed and plodded on, both amused and disappointed. It serves you right, she told herself. You know better than to expect a butterfly to know your name. All they know are songs and poetry, and anything else they hear. They mean well, but they can’t keep things straight. And why should they? They die so soon.
The butterfly swaggered before her eyes, singing, “One, two, three o’lairy,” as he whirled, chanting, “Not, I’ll not, carrion comfort, look down that lonesome road. For, oh, what damned minutes tells he o’er who dotes, yet doubts. Hasten, Mirth, and bring with thee a host of furious fancies wherof I am commander, which will be on sale for three days only at bargain summer prices. I love you, I love you, oh, the horror, the horror, and aroint thee, witch, aroint thee, indeed and truly you’ve chosen a bad place to be lame in, willow, willow, willow.” His voice tinkled in the unicorn’s head like silver money falling.
He traveled with her for the rest of the waning day, but when the sun went down and the sky was full of rosy fish, he flew off her horn and hovered in the air before her. “I must take the A train,” he said politely. Against the clouds she could see that his velvet wings were ribbed with delicate black veins.
"Farewell," she said. "I hope you hear many more songs" — which was the best way she could think of to say goodbye to a butterfly. But instead of leaving her, he fluttered above her head, looking suddenly less dashing and a little nervous in the blue evening air. "Fly away," she urged him. "It’s too cold for you to be out." But the butterfly still dallied, humming to himself.
"They ride that horse you call the Macedonai," he intoned absentmindedly, and then, very clearly, "Unicorn. Old French, unicorne. Latin, unicornis. Literally, one-horned: unus, one, and cornu, a horn. A fabulous animal resembling a horse with one horn. Oh, I am a cook and a captain bold and the mate of the Nancy brig! Has anybody here seen Kelly?” He strutted joyously in the air, and the first fireflies blinked around him in wonder and grave doubt.
— an excerpt from The Last Unicorn, by Peter S. Beagle.