A/N: Written for the amazing Queenswatchcat! I hope I filled this adequately, it took a bit of a different turn than expected.
Also I've started writing the sequel to Unpolished Silver, fret not.
The familiar tinkling tone interrupted Sebastian in his diner preparations, having just lain out the diningware for the table. He stepped in the doorway of the earl's study, the scene before him cast in late afternoon light streaming through the window. Ciel was hunched over his desk, scribbling furiously on a fresh sheet of paper. This was not an unusual scene, the boy did his Funtom correspondence at this hour. The curiosity lied in the smudged and crumpled drafts carpeting the space around the desk; the boy could always convey his regards elegantly on the initial try, this was unprecedented.
"Yes, my lord?"
The boy glanced up from the newest smudged letter, the frustration in his brow melting to doubt. Sebastian merely cocked an eyebrow, silently waiting for the boy's requests. The pen was placed on the desk and the piece he'd just finished was quickly added to the mess on the floor.
"I need your assistance with this letter," Ciel sighed, resting his cheek defeatedly in his ink stained hand.
"Forgive me for questioning you, my lord," the butler said and bowed at the waist, "but I'm curious what's unique about this letter, as you've had no difficulty in the past."
Ciel downcast his gaze, "It's a personal matter rather than of business, of which I do not excel."
Sebastian's eyes widened for only a moment and then he gave a knowing nod. His master was so reluctant to show vulnerability or emotion, and at this moment he freely exposed both. This endeavour would prove interesting at the least.
Sebastian stepped out of the doorway and stood beside Ciel behind the desk, his eyes trying to make out the words on the discarded attempts. Ciel cleared his throat.
"Must you come so close?" he sounded irritated underneath his authoritative tone.
"Only to have a proper conversation, young master."
"Maybe this was a foolish idea," the boy grumbled under his breath, "I doubt demons know the nature of love."
"Ah, so it is a love letter?" the butler cooed, his lips quirked in amusement.
Ciel glared at his butler in astonishment, having momentarily forgetting the demon's acute hearing. He swallowed his embarrassment and replaced it with anger, hands grasping his desk as though he were going to storm out at any moment. Sebastian pulled his glove off with his teeth and licked the pad of his thumb. He bent close to the boy and gently rubbed at the dark smudge on his cheek.
"Who is the letter for?" Sebastian said silkily, before the boy could react to the first question or his servant's undignified behavior. In a mere moment he had replaced his glove and had his hands once again at his sides. He appreciated the color dusting the boy's neck, threatening to creep higher.
"It's not-it's for no one," he spat, "It's a practice letter."
"But that will not do, young master. You cannot write a practice love letter without a subject, perhaps that is the cause of your struggles."
"I suppose you're right," he huffed, relieved he'd evaded the question.
"As we'll need a subject, you can use me," Sebastian said, careful not to let his face reveal how much he was enjoying this game. He could tell the boy was hiding something and very much intended to figure out what it was.
The boy shot him an indignant look, the same one he gave when Sebastian suggested he be the one to teach the earl to dance. He had taken this look to be simple resentment, but in this context he could feel that it ran much deeper. How delightful. Annoyance, embarrassment, and fear.
"What are you staring at?" Ciel growled, standing from his chair to look up at the servant.
"I'm trying to understand why you are afraid of writing this fake letter about me," he responded, still searching his master's sapphire eye. The fear raged through it now, the devil's ears could even detect the change in Ciel's heartbeat, now pumping with adrenaline.
Sebastian knelt down and picked up an unsmudged paper and uncrumpled it carefully.
"I do not proclaim to know why or how, only that I know it is the truth. I've lost sense of who we are as separate people, only knowing what we are together. I am in love with you, Sebastian," the demon read aloud, Ciel burying his face in his hands.
The butler once again stood in front of his master, placing the confession on the desk.
"Young master," he breathed, his suspicions confirmed.
"Don't," Ciel said like the word burned his lungs.
"How foolish-" Sebastian whispered, and Ciel turned to leave.
"-and beautiful," Sebastian said as he turned the boy around and kissed him.