My sister and I were best friends.

I was born with sickle cell anemia, a disorder that left me with chronic pain and intense fatigue as a child. A blood or bone marrow transfusion was too expensive for a great deal of my childhood—my mom worked two jobs trying to save money for any kind of surgery. It got to the point that by age eight, I couldn’t really attend school regularly anymore.

On days I felt up to it, I’d attend classes over Google Meet on my mom’s old beat-up laptop that was glitchy and unreliable. And of course, like any child suffering from a debilitating disease, I was miserable as all hell—I missed my friends and I mourned my loss of physical capability. The only person that really kept me going was my sister.

She was older, though now that I think about it I’m not sure by how much. She couldn’t have been an adult, or else there was no reason why she didn’t have a job to support the family, but she certainly wasn’t a child. Though these were unimportant details to me as a sick, lonely ten-year-old.

My sister’s name was Madeline. Her skin was sallow—even more so than mine, which often took a yellowish hue—and paper-thin, stretched tight around her skull. Her eyes bulged out as if her sockets couldn’t quite hold them, and her lips were often cracked and bleeding. In other words, she looked as if she were on the verge of dying, which is perhaps the reason that she was at home with me all the time.

Madeline loved to play tricks on me. In the middle of the night when I would get out of bed to use the restroom, she would hide under my bed and grab my ankles with her cold, bony hands. This led to me being too wary to leave my bed most nights, and caused me to piss myself even more than usual for a child with my disease.

Now that I think about it, she loved to scare me. Sometimes, I’d wake up to her face pressed up right against me, her ghostly eyes wide and staring into mine, her breath rattling in my face with an awful stink—I don’t think she ever brushed her teeth, at least not on a regular basis.

One of my clearest memories is of the night that I came back from the kitchen, where I’d gone to grab a midnight snack, only to have Madeline seize me by the throat and slam me against the wall, chanting, “Kill you, kill you, kill you” over and over again as she cut off my airway until I nearly passed out. Then, at the last second, she released me suddenly and flew under the bed, hissing like a cornered animal, her hair flying behind her.

I still remember the smallest details of that night—the blood that ringed her mouth like cake frosting, dried and peeling; the way she panted; the clumps of hair missing from her skull. I was too terrified to ask her what was wrong, and by the next morning, everything had returned to normal—as normal as life could be with an older sister who loved to psychologically torment you.

Looking back on it now, I’m positive that she didn’t mean any kind of harm. At least most times. There was the odd occasion: that night that she tried to strangle me, for instance. And others that aren’t as clear in my memory…I still remember her standing over me in the bathtub, a greedy light in my eyes as she shoved my head under the water, over and over again. The oily imprints her fingers left in my hair.

Around the time that I went into puberty, Madeline’s jokes stopped being funny. Not that they ever were, it was more that…Madeline stopped being a friend to me, and became more of what you’d expect an older sister to be: annoying as hell. Although I hope that most kids aren’t as terrified of my sister as I was.

I became quite the tattletale as a twelve-year-old. Call me immature, but so would any other tween at my age. The moment I heard the front door open, I’d run to the foyer and blab to my mother. “Moooom, Madeline hasn’t taken a bath in two weeks. She told me herself.” “Moooom, Madeline wouldn’t let me lie down all day, she screamed at me whenever I tried to go to sleep.” “Mooom, Madeline’s doing the thing with the rats again.”

Now that we’re on the subject of rats, they were Madeline’s favorite animals. She was obsessed with rats. And living in a weathered old building with hollow walls and a spacious attic didn’t help much. Especially since my sister was always leaving treats out for them.

On my thirteenth birthday, I woke up to Madeline dangling a live rat over my face. Its fur was a sooty black and riddled with mange, its gray feet squirming, emitting squeals as she swung it playfully by its wormlike tail. Of course I yelled and jumped back, slamming my head against the wall, which of course startled my sister enough to drop the rat on my bed sheets, and it instantly began crawling up my body.

The feeling of its grimy feet was enough for me to lose my mind. I screamed and thrashed as if I were on fire, whacking at it with my hands until finally I knocked it to the ground and it scurried off to its hole somewhere.

That whole time, my sister had been glaring at me as if I had just murdered all her friends. “You’re gonna pay for that,” she intoned, and her voice seemed to grate, sounding much deeper than it actually was.

Ever since, I’ve had night terrors every night. They involve rats sometimes, but it’s not regular enough to say that Madeline cursed me or something. Besides, that’s ridiculous. She was just a girl. A girl with some very strange interests.

And I mean weird. It wasn’t just the rat thing. She had a passion for everything disgusting. When I was really young, she had a morbid fascination with serial killers, particularly the ones that ate their victims, like Albert Fish or Boone Helm. She’d study them with an unrelenting fervency and then draw cute little storybooks about them, complete with graphic pictures. And Madeline was no mediocre artist. To this day, I’m still terrified of even the smallest amount of blood; it makes me think about those gruesome drawings: Jeffery Dahmer ripping apart a little boy with his bare hands, unraveling his large intestine; Albert Fish cutting off Thomas Kedden’s penis and shoving the bloody stump down his throat, mouth gaped unnaturally wide.

God.

Another interest of her for a while was medieval torture methods. Iron spiders, breaking wheels, iron chairs, thumbscrews, garrotes—the gorier the better. She was particularly fond of spiked punishment collars, which, if you don’t know, are five-kilogram iron bands studded with razor-sharp thorns that skewer the victim’s neck and cause excruciating pain until an eventual death from gangrene.

She spent several weeks trying to recreate one, and at one point tried to pressure me into wearing it. She even drew me pictures to try and convince me how “handsome” I’d look wearing it. I can’t get those drawings out of my head—vivid images of me with metal spines buried in my flesh, my tongue lolling out of my mouth, eyes wild and bloodshot, covered in my own blood.

Oh, and she loved dissecting animals. I don’t remember how many times I’d walk into my room and find dead animals on the floor, their stomachs slit with organs spilling onto my floor, already crawling with ants.

Now that I’m older, I wonder if she was possibly autistic, and maybe she just had some weird special interests. But somehow I know it’s not that.

It took me a long time to realize my childhood wasn’t normal. I wasn’t ever told, really—it wasn’t like I went up to people all like, “Haha, older sisters are so annoying when they give you hyper realistic drawings of your torturous, violent end for Christmas, am I right?” I think the actual solid realization came when I went with my then-girlfriend to visit her family, and her little sister ran up to her and hugged her tightly, eagerly talking her ear off, and my girlfriend alternatively hugged her back and teased her with a gentle, adoring smile on her face.

In my head, I was thinking, Oh, shit. I would have never done that to Madeline.

I think around the time that I finally got my blood transfusion is when Madeline just sort of…disappeared from my life. It was a slow, gradual thing. In my head, I chalked it up to her growing older. Maybe she’d moved out, gone to college, that sort of thing. I have distant, unclear recollections of writing letters to her, but how can that be possible? I didn’t know where she was, what she was doing.

I visited my mom about a month ago to see how she was doing. She’d had her first stroke by then and doggedly refused my sly attempts at getting her into an assisted living center. She made some offhand comment at one point, saying something along the lines of, “I’m so glad you never had siblings, another you would’ve been a nightmare,” and I said, “Wow, forgot about Madeline already?”

She laughed. “I didn’t know you remembered Madeline. You stopped seeing her when you were fifteen. I was about to go get you checked out.”

“Checked out?”

“I’m not criticizing you, hon, but it’s not all that normal for a teen to have an imaginary friend.”

My first reaction was confusion. “She wasn’t imaginary. She’s my sister.”

“Oh boy.” My mom paused with a spoonful of chicken stew halfway to her mouth.

“Whaddaya mean, ‘oh boy’? My sister.” I was getting worried. “Mom, do you have amnesia or something? I think we should get you checked out.”

She wrinkled her brow. “I swear to god, you never had a sister. And I know it’s not just my old age getting to me. I can show you the birth certificates and everything.”

I didn’t even know what to say. She saw the look on my face and continued, “Hell, you can even ask your dad! He was there with me when you were born.”

“...Huh?”

“It’s actually kind of funny that you think that,” she said, more to herself than to me. “I did tell you that you were almost a twin, didn’t I?”

“Yeah, you’ve mentioned,” I said, thinking, She’s completely insane. “How ‘almost’? What do you mean, ‘almost’?”

“There were two of you, but, uh, one of the fetuses just vanished.” She waved her hand. “Like, it was weird—no bleeding, no anything. Just disappeared. The doctor says you probably ate it, you know. Or absorbed it, whatever.”

“But you have to remember Madeline.”

“I remember you talking about her all the time. But I don’t remember seeing no Madeline, except for those pictures you drew.”

We eventually ranged off topic, though my mind didn’t once stray from my sister. Before I left, I asked her if she kept any of the supposed pictures, and she vanished into her bedroom for a while before digging up a dusty cardboard box and plopping it down in front of me. “Go ahead and look if you want.”

I said my goodbyes and returned to my car before I began to pore over the contents. Journal entries, sticky notes, vague scribbles, drawings. I don’t remember all of it, because there was a lot. But things stand out to me:

The pictures I drew of Madeline, who looks exactly as I remember.

Diaries describing days spent with only myself for company. Diaries describing the rats in the walls. Diaries describing cannibals. Diaries describing torture.

And at the very bottom, in a manila folder decorated with crayon drawings of stars and smiley faces, were sets of Polaroid photos.

Overhead shots of animals being gutted, of my own fingers pulling back strips of flesh to reveal the viscera and gore inside. Images of every stage of making a crude punishment collar. Snapshots of every page of a storybook describing Boone Helm killing his cousin, eating people. A drawing of Jeffery Dahmer bending over a bloodstained victim.

No recounts of Madeline anywhere, except for three drawings.

Oh god. Oh god.

What have I done?