Sebastian x Child! Reader: Beautiful Monster

It was almost midnight, and you were wide awake. 

You had been asleep- happily and blissfully unaware of the world around you- and then just as suddenly you were gasping for air and crying out. For several moments you cried into yourself- rubbing your little chubby hands over your now tear-stained face- before you could even remember why you were scared.

It had been a nightmare that'd woken you up. And a nasty one at that. 

Slowly the dream began to come back to you, and you instantly cried harder. It was horrible and there was no way you'd ever be able to go back to sleep again.

For a moment you stood in the dark hallway, looking between the two corridors on either side of you, your fear of the darkness making you breathe heavily. Left or right? That was the question. You only pondered for a brief second, wondering who you should go to, before you ran to your left- leaving your parents’ bedroom far behind and running to the end of the hall where a single door resided- secluded from the rest of the floor. You knew that he might not be happy with you if you intruded, but as your little mind raced with horrific memories of your nightmare, you found that you would rather face his anger than suffer on your own.

So with a hesitant hand, you moved to open the daunting door, and entered before the nightmarish monster could find you.

*

“Mistress (F/n),” Sebastian immediately moved away from his window, looking somewhat concerned. “Are you alright?”

From her place by the doorway, the little girl of six cried gazing at him with watery (e/c) eyes. “S-S-Sebastian!”

Then, without another word, the child ran forward and buried her face in his pant leg, sobbing until her whole body was quivering with fear. For a long moment, Sebastian watched his Masters’ daughter- calculating the situation- before reaching down one of his hands and gently beginning to stroke her hair.

“Whatever is the matter, little one?" he asked. "And why are you out of bed at this hour? It's long past your bedtime, and your parents will be upset if you are not well rested."

From where she was buried in the fabric of his pant-leg (F/n) choked out a reply. And as she did so, Sebastian was fairly certain that if he hadn’t had his demon senses, he never would have been able to hear what she was saying. 

“I-It was s-scary,” she gasped, holding onto him for dear life. “I-It was going to g-g-get m-me!”

Sebastian cocked his head ever so slightly to the side. “Mistress . . . did you have another bad dream?”

“The monster almost got me this time, Sebastian.”

The Butler’s wine colored eyes studied his young mistress thoughtfully. "In your dream?"

“Yes,” the child said quietly. “It was horrible! He was hurting mommy and daddy . . . and you.”

Sebastian knew that Ciel’s daughter had long since grown attached to him- there was hardly a day that passed that the child didn’t ask him to tea- but he had never thought she would truly worry for him.

To have concern for someone in a dream was a subconscious warning, a signal that the sleeping mind concocted to tell the dreamer specific things. It was a safety mechanism that most humans had, and apparently (F/n) had somehow triggered hers. Perhaps she had seen something of the future that awaited her father when his contract came due, or maybe she had somehow been blessed with a sixth sense. Whatever the case, Sebastian instantly moved to calm her fears, as any butler worth his salt would have done. 

“I would never let any harm come to you or your parents, Mistress.” Sebastian vowed. “Long before you were born, I made a vow to your father, which means I will always watch over you.”

(F/n) shook her head, and looked up at the Butler with disbelieving eyes. “Nobody can fight monsters, Sebastian. Not even you.”

The Demon smiled. “Is that so?”

The child nodded.

With a tight-lipped smirk, the butler lifted the girl’s babyish chin with his forefinger, making her look him dead in the eye. “But what if I told you that I was a monster too?”

The child frowned. “You aren’t a monster, Sebastian.”

Sebastian’s lifted an eyebrow. “Oh but I am, Mistress. Though because of my promise to serve your father, I must behave myself.”

For a long moment the child stared at him with large eyes, and the Demon had to repress a laugh. Though as she looked at him, Sebastian felt the smallest pang of regret. Now that she knew the truth, there would be no going back. His little Mistress would be afraid of him, and Ciel would end up finding out sooner or later. It would most certainly be a problem in the future. 

But then, (F/n) spoke and once more Sebastian Michaelis was surprised.

“Show me.”

“I have no desire to frighten you, little one.”

“Please. . . I want to see. . .”

Sebastian continued to stare into the child’s bright (e/c) eyes for a long moment, before he inclined his head. “As you wish . . . my young mistress.”

Then, in the mere blinking of an eye the Butler’s eyes began to glow an unearthly shade, and his pupils became slender and animalistic. His hair floated about his head in a stunning halo of raven strands, and the pentagram upon his ungloved hand began to shine. The air seemed to grow heavier with this transformation, and the demon internally sighed. Despite what it would mean, it felt good to let his control go- even if it was for but a moment. 

(F/n) was silent as she gazed at her Butler, taking in the change with the innocent eyes of a little girl. But instead of running away, or screaming, or crying, the Phantomhive child smiled up at him shyly.

“You have beautiful eyes for a monster, Sebastian.”