From a writing prompt

Actual writing ahead!
A short story/ flash fiction from a prompt. A closed writers' group on Facebook hosts this thing.

THE TWINS AND THE PIT

“Sometimes, love means clinging on to someone, and sometimes it means letting them go.” I flex my fingers around her hands.

“No! You promised not to let go,” her eyes widen, her attempt to sound authoritative overridden by the fear oozing from her voice.

“But when you love someone, sometimes you have to let go,” I manage not to laugh, to keep my voice serious.

Her fingernails dig into my skin. “You will not drop me. I'll tell mom about your box.”

“What box?” I tighten my grip. The kids behind me light up with chatter.

She smiles up at me, her hands relaxing. “Seventh floorboard from the door. I took a video of what's in there. And I backed it up on my friend's cloud drive. Oh, and I have another of you from last Tuesday, when you added to the box. It's not clear what's in that bag you were carrying, but you take it to your room, and then there's the sound of the board moving, and then you come out with an empty bag and insult me. Mom will certainly put it together.”

“Slimy twit! You're not supposed to spy on me.”

My twin sister rolls her eyes. “Pull me up. We've won.”

“Which friend?”

“What?”

I let go of one of her hands. “Which friend has the backup copy?”

“You're not going to let me fall!” Her dropped hand reaches for me. She tries to yank herself up. We both know she can't.

The kids behind me snicker until I turn my head toward them. “Anyone not wanting to land in the pit should leave. Now.”

No one doubts my resolve. They run like roaches from the light. I turn toward my twin.

“If you drop me, mom will ask what happened, and I'll tell her why you let me fall.”

“When I drop you, it'll take time for you to get out. And you'll be covered in the goo of the pit. I'll get home first. I'll tell mom you jumped, and that you've been planting evidence against me. I'll show her the box and say it's yours. That I was keeping something else in there. Her mind will be made up before you get home.”

“No! No, you can't do that. Help me up. Just help me up. I'll get rid of the videos. And the backups.”

“And you won't spy on me again?”

She shakes her head. A tear slips out and rolls down her cheek. It drops to the goo far below.

But what is one tear compared to wax, mud, decaying plants, bits of trash, and thousands of insects? They say the pit was once for swimming in. That important people raced around in it, back when it was full of pristine water. Back when there was so much water that people wasted it for things like that.

Now we just hold each other over it and see who can keep their partner from falling in the longest. My sister and I hold all the records.

“Which friend has the backup?”

“Sett,” my sister answers with a huff.

“Poinsettia? You gave her the backup copy? Why her?”

“Like she's storing anything else on her cloud? Besides, she's the only one who wouldn't turn on me and blackmail you herself.”

“No, Fuzzbrain, I'm the only one who wouldn't turn on you.” I lift my sister up. She's clean, as always, because I've never let her fall into the pit. And I never would. But she doesn't need to know that.

“Why do you have that stuff in the box, anyway?”

“You aren't old enough to understand.”

She punches my arm as we walk home. “I'm the same age as you, Troll.”

“I've matured faster.”

“You wish. Race you to our front door?”