You did not realise, when you started, how much you would lose to your other self.
The (potion, medicine, drug) is vile as it slips down your throat, and it burns and burns and you double up in the pain, clutching at your stomach and then your head and it's not like you didn't expect this anyways. Because your body is breaking within you and fitting itself to someone else, something else, and Hyde smiles at you in the mirror, charm and innocence and you really can't see anything wrong with that.
He holds his hand out, an offer.
The first time is always the hardest. You wake up, slumped over the work table in your lab, chemicals and glass scattered about you, and you can't quite recall, but you sit up, shaking and all the more tired for your trouble, and your timepiece reads nine, and the mid-morning sunlight shines through the grimy window.
In the mirror, Hyde brushes the hair from your eyes, smooths it back from your forehead, straightens your glasses-leans in close, whispering tales in your ear that you can't quite bring yourself to believe.
A breath of air against your ear, you shiver, paralyzed with fear and not stupid enough to turn around.
In the mirror:
A pair of arms around your waist, pulling you close. Hyde rests his chin on your shoulder, dark eyes filled with something that might have been pity.
Don't be afraid of me, he seems to say, and a smirk coils across his lips. I'm only what you want me to be.
You look away.
But it's lonely, sometimes. Being alone. And though that sounds terribly redundant, you've never felt quite lonely before, not like this. You have your servants, yes, but they're practically furniture. You have friends, but you haven't seen Lanyon in years, and Utterson would never understand.
I understand, whispers Hyde somewhere in the back of your mind.
And you know he does, and perhaps that frightens you a little.
You take a breath.
In the mirror, a single pomegranate seed passed mouth to mouth.
(Hyde tastes like promises.)
(Be careful what you wish for.)
And slowly, you begin to believe him—because Hyde has done horrible things that you understand now must have lurked in the back of your by no means lacking imagination (you dreamed him up, after all, didn't you?). It's horrifying, really, but—isn't that the point? Hyde can do things you cannot, can never do for fear of reputation.
And the next morning, he fills in the holes in your memory with his saccharine voice.
You can see him today. Curled against you, the red silk sheets draped across his body, pooling at the undefined edges where he ends and you begin.
And it will happen like this:
The sheet will slither from his body, and you will embrace and he will whisper in your ear—
(here let me show you)
He covers your mouth with his own, and his skin is hot against yours and your blood runs cold in the heat of the moment.
Slack-jawed, you lie there, lifeless, a rag doll for him to play with.
He touches you. Trails his thin pale hands down your hips, licks at the base of your throat, marks you for his own.
Your eyes glass over.
Love makes you a fool, Hyde purrs into your ear.
"Yes," you say, and look into the mirror.
You shiver. Draw the red silk sheets closer around your body, curl in on yourself, and if you close your eyes you can still see a Hyde-shaped space burned into the insides of your eyelids, long fingers stroking through your hair in the afterglow.
Shh, he whispers, as you flinch and draw away. It's only me.
When you were ten, you thought there was a monster living under your bed.
(The funny thing is, it's only now that you're realizing he's in it.)
and it goes like this:
In the morning:
Hyde rises from your bed, hair tousled and dressed all in a too-big nightshirt; it slips from one shoulder and hangs off of his tiny frame, and—
And he is alone.
And he is real.
And he looks, into the mirror, and your face peers back at him in terror, tired and drained and too weak to stand. You slump against the chest of drawers, and in the mirror, he sinks down with you, cups your thin face in his long hands, caresses—
"Oh, Henry," he says, and laughs, and revels in the sound. "I think it's about time I had my turn, hm?"
razor-sharp teeth grazing your lips, the taste of him metallic in your mouth, pouring down your chin, red red red—
(Hyde tastes like pomegranate.)