I was only seven when I started to see her.

She was my reflection, but not. She was my shadow, but not. For years I thought she was my sister because she was always there. I could see her, but I also couldn’t. 

She’s like that shadow in your periphery. The thing you chase in your dreams.

Or perhaps the thing you run from.

I was thirteen when she started talking to me. She gave me advice, like a sister. She told me we were sisters.

Soul Sisters.

Two souls who shared the same body. I was in control, but she was in my head. That shadow I could never really focus on but still see. Still hear. Still feel.

Her name was Cast, and she loved me.

“Don’t worry; we’ll be together forever,” she promised, her voice a lilt on the wind that only I could hear.

“I know,” I would always say, relishing in this feeling of stability. Of togetherness.

Forever.

She would never leave me. Never.

When I was eighteen, things started to change.

Cast would tell me things. Things about people who secretly hated me.

Smiles started to look like smirks in the hallways of my school. Laughter from my parents sounded mocking to my ears. Even best friends began to feel like rivals.

Only Cast was constant. Only Cast loved me.

“Selena, do they really know you? If they did, would they love you? What about those thoughts? Those thoughts in your head about hurting them? Killing them?”

She was right. My thoughts were growing dark. Tainted. I wanted to hurt those who hurt me.

Make them bleed.

When my twentieth birthday came, I left home. Left those smirking faces, secret rivals, and laughter directed at me.

It was just us. Cast and me.

Forever.

But the thoughts didn’t stop. My neighbor hated me, even though she grinned and waved whenever she saw me. My landlord was making me overpay. Everyone was an enemy.

Except her.

“No matter what, I will protect you.”

She would protect me.

No one would hurt me.

No one.

But what happens when you begin to see a face in the mirror beside yours? A face that isn’t smiling or reassuring you.

It’s frowning.

It’s taking my friends, my family, my sanity.

What happens when a Soul Sister starts to take over?

Maybe you’ll find yourself like me; friendless. Unhappy. Paranoid. Sad. Angry.

And worst of all.

Alone.

“We’ll be together forever, Selena.”

Forever.

But what happens when forever seems too long?