Warnings: implied sebaciel, slight gore. Honestly, Sebastian is a creepy, hungry demon, what did you expect?
Inhale. Exhale. It was an unnecessary set of motions for the demon, for he needed to breathe like he needed to sleep, which is to say he didn't. Over the centuries, he had found that humans find it rather unsettling when one doesn't breathe for extended periods of time, especially when one is feigning sleep, so he began to breathe at all times to better blend in. The fact that he could smell at all times the wide variety of scents his keen senses could pick up was just an added bonus.
Especially with that boy as his master now.
To breathe in the scent of his soul too deeply when it swirled thickly about him was torturous ecstasy. With pride and arrogance layered over a foundation of despair and innocence, the young master's soul was a constantly changing masterpiece, its dynamics and complexities shifting from day to day with his moods. The young master was a flower coaxed to bloom beneath his hands and Sebastian wanted to bury his nose within his depths and drown in him.
Mornings were at once both the best and worst times to be around the young Phantomhive boy. The scent of his soul, having collected like dust on the sheets, would rise up into the air and assault the demon's senses as the boy stirred in his cocoon of blankets. In the space of time between first rousing the young master to greet the day and turning around after tying the curtains open, Sebastian would invariably breathe in deeply, letting the glorious aroma wash over him, and swallow thickly before composing himself, keenly aware of the ache in the void that served as his stomach. The space of time between the boy's initial awakening and the full placement of the young master's mask of cool composure was equally as torturous, when the boy was sluggish and vulnerable within his dissipating haze of sleepiness. Sebastian had to present the young master's tea and lay out the schedule for the day in pleasant tones when all he wanted to do was throw the covers back and slot himself over the boy and nuzzle his face up beneath that round and sleep-warm face, sinking his mouth down onto soft flesh and laving his tongue over smooth skin where the scent of the boy's soul would surely be so thick as could be tasted and proceed to coax more of it up through the skin into salty sweat.
But that could wait until later, when adolescence consisted of more than thin threads sparsely woven through the boy. To do so now would shatter the delicate trust so carefully built up over the years and Sebastian would much rather build up the tension when the time was right and convince his master to make the first move.
Bathing the young master in the evening was almost as bad as waking him up. The scent of the boy would rise up with the steam, enveloping the butler in a cloud smelling of the boy's soul, forcing him on many occasions to smother the urge to bend down and lick up the water droplets sliding down the boy's skin. Sebastian had taken to using only soaps and shampoos that would complement the scent of the young master's soul, mostly using light flowery scents, along with other light, sweet scents, scents that were generally more suited to the fairer sex. He certainly wouldn't use soaps more suited for men; he had bathed the young master with one such soap only once and had immediately decided that it clashed horribly with the young master's natural scent and would never be used again.
Twice the young master had called Sebastian out on his habit of breathing deeply around himself, both times when the boy was getting settled in for bed. The first time, towards the beginning of their contract, Sebastian had responded by saying that he simply could not resist breathing in his tempting scent. The second time, a couple years later, Sebastian had simply smiled with a hint of fang and said, "All the better to smell you with, my lord."
"Tch. Bloody demon," the boy had muttered, turning onto his side and pulling the duvet up over his shoulder.
It was easier for Sebastian to play the role of the perfect butler during the day, when the young master didn't look as vulnerable as he actually was and tasks were demanded of him imperiously and impatiently. He could easily play the game of provocation and placation under the guise of a well-meaning and obedient servant and breathe in the roll and swell of the young master's emotions as they shifted from irritation to frustration to proud satisfaction to concealed contentment.
At night, however, the boy was weary from the stresses of the day and allowed himself to lower his guard a little around Sebastian, a mistake on his part for it encouraged Sebastian to lower his human guise and push the boundaries of their master-servant relationship bit by bit. It was highly entertaining for Sebastian to play with the boundaries of the young master's comfort zone during these times when he was preparing for bed. He could gently poke and prod at the boy to see how much he could tolerate and when he would snap at Sebastian to cease his nonsense and then relish in the waves of irritation rolling off of him. When the banter ceased and the boy settled into soft sheets in a bed far too big for such a tiny creature and the boy's face smoothed out into placidity in readiness for the sweet oblivion of sleep, that's when the last daily test of the butler's restraint began. All he had to do was walk the few short steps to the doorway and step out of the room, but the feel of his master's soft flesh during the bath earlier and the scent of his soul had the demon wanting to shed his human guise entirely and go back to the bed and cover the boy's body with his own. He wanted to sink his claws and fangs into the boy, lick the blood from the wounds, taste every pale inch of his flesh. He could teach the boy the real meaning of the word 'tease'; he could slice the boy open to lick at his entrails and then seal him back up; he could make the boy long for nothing but him, body and soul; he could –
He could wait. There would be a time when he would be able to satiate all his desires regarding the boy. In the meantime, he would have to continue to be the perfect butler and keep his master in the dark about what he wanted to do to him. His self-control was absolute, there was no room for error.
The most satisfying part of his role occurred at the climax of select missions from the Queen, when the young master's cold, logical mind gave way to panic and fear and Sebastian could step in and shelter the boy with great black wings and dove white gloves, imploring the boy to give him an order, any order. With that marked eye exposed and glowing, the boy would invariably call his demon's bestowed name repeatedly and desperately cry out an indisputable order. With the smell of his master's desperation, fear, and crumbling pride settling thickly in his nose and on his tongue, Sebastian couldn't - wouldn't - disobey such an order and would subsequently promise his obedience with an emphatic statement of those three little words. As the dust cleared after he carried out the order, Sebastian could finally, finally pick up the small, crumpled form of his master and cradle him against his chest as Ciel buried his face in his shoulder. It was then that Sebastian could bend his face towards Ciel's hair and breathe in deeply of his soul: the shivery echoes of desperation and fear, the misery, the sting of swallowed pride, the bitter acceptance, and the determination all wrapped up into one torturously glorious aroma; it was delicious and he wouldn't be able to suppress a soft satisfied purr. It all made him so very aware of the deep-seated ache of hunger in his core and eager to see the end of this contract.
But he could wait patiently for that day; he was having too much fun playing butler, after all. Until that day he could finally consume his master's soul, he would continue to guide and carry him through the dark, breathing him in.