So I was listening to Schubert's "Erlking" when this idea popped into my head. Enjoy! Note: I'd say Ciel is around ten. Let's assume for the moment that Ciel's parents never died, and he never formed a contract with Sebastian.
Who rides so late through night and wind? It is the father with his child. He has the boy well in his arm, he holds him safely, he keeps him warm
Vincent Phantomhive sat in the carriage, holding his young son, Ciel, tightly in his arms. It was a dark, stormy night with howling winds that rocked the carriage violently as they headed back to the Phantomhive estate. Vincent observed the weather quietly for a while before he noticed that Ciel was clinging to the front of his shirt tightly, burying his face in the man's chest and shivering.
My son, why do you hide your face so anxiously?"
"Father, do you not see the Erlking? The Erlking with crown and tail?"
"My son, it is a wisp of fog."
"Ciel? Are you alright? What's wrong?"
"Th...there's a demon in the carriage with us. Can't you see him?" Ciel murmured, glancing anxiously over at the tall, raven-haired man that was observing him with a cruel smile. Vincent rubbed Ciel's back soothingly.
"It's a foggy night, Ciel. The mist is playing tricks on your eyes, nothing more." Ciel shivered again, knowing full well that the man sitting across from him was no illusion. The demon smiled sweetly and spoke, his voice soft and a hand outstretched towards the boy.
"You dear child, come, go with me! Very lovely games I'll play with you; some colourful flowers are on the beach, my mother has some golden robes."
"You look so cold and frightened over there, darling Ciel. Why don't you come sit on my lap? We could play peek-a-boo to ease your fears." The man produced a rose in his hand and offered it to the boy. "You can keep this flower if you want. Come, I'll wrap you in my arms to keep you warm." Through his honeyed words, Ciel saw the demon for what he really was, and knew that he had to stay away, no matter what.
"My father, my father, and don't you hear what the Erlking quietly promises me?"
"Be calm, stay calm, my child; the wind is rustling through withered leaves."
"Father, can't you hear the demon whispering promises to me? He wants me to go with him! You can't let him take me away, you can't!" Vincent continued to rub his son's back soothingly.
"Ciel, there's nothing to be afraid of. It's just the wind rustling through the leaves. There's no demon, you are safe, Ciel." Vincent frowned as he held the shivering child. Maybe Ciel had a fever. It was a cold evening, and he might not have been dressed warmly enough. Vincent would have Tanaka call a doctor when the got home, just to be sure.
"Do you want to come with me, pretty boy? My daughters shall wait on you finely; my daughters will lead the nightly dance, and rock and dance and sing you to sleep."
"Are you going to come with me, my sweet Ciel? I'm offering this to you, and only you. I will lead you in a lovely waltz in an exquisite ballroom, and when you grow weary, I will hold in my arms, and sing you a soothing lullaby to help you sleep. Well, what do you say?" The demon's voice was sweeter than ever, but Ciel knew he was becoming impatient.
"My father, my father, and don't you see there the Erlking's daughter's in the gloomy place?"
"My son, I see it clearly: there shimmer the old willows so grey."
"Father, please! He's holding his arms out to me! Keep him away from me, father, keep him away!"
"It's alright, Ciel, I see it. The old willows certainly do look as though they have arms, don't they?" The demon's eyes glowed a startling shade of pink as he reached out and wrapped his arms around the small child, pulling him into his lap. He gently stroked the boy's face while he spoke.
"I love you, your beautiful form entices me; and if you're not willing, then I will use force."
"My father, my father, he's grabbing me now! The Erlking has done me harm!"
"How beautiful you are, my darling Ciel. Your sweet soul and delicate body entice me with every movement. But since you won't come to me willingly, it seems I'll have to take you by force." The demon locked his lips onto Ciel's in a sweet kiss and began to devour his soul while the boy writhed beneath him. With the last of his voice, Ciel called to his father.
"Father! Father, please! Help me! It hurts..."
The father shudders, he swiftly rides on, he holds the moaning child in his arms...
Vincent shuddered, something was definitely wrong with Ciel. He urged the driver to go faster, and held Ciel tightly in his arms as he struggled and moaned. "We're almost home, Ciel, just a little longer," he silently begged. As the carriage slowly rolled up to the Phantomhive estate, Vincent noticed with a sudden feeling of dread that Ciel had stopped moaning, and hadn't said anything about the demon recently. There was no need, for the demon was long gone, and with him, Ciel Phantomhive.
He reaches his farmstead with toil and dread,
The child in his arms lies motionless...
Dead.
Oh, wow! This came out better than I'd ever hoped. Yes, the Erlking was Sebastian Michaelis, even though I never said his name, it was fairly obvious, I thought. Yes, I should be working on A Change of Plans, and I am, in fact, I think I'm almost done the chapter, but I had to get this out first. Absolutely had to. Anyways, 'till next time! This is 1000 words exactly...