She’s trailing her IV with her. I can barely move, so she shouldn’t be up, but Tila doesn’t let a small thing like pain stop her. I’m surprised she hasn’t triggered the alarms. She probably disabled them—she’s always been clever with her hands.

We’re not supposed to see each other for a few days, so we grow used to being separate. As usual, she’s ignored all the rules and advice and followed her own heart. It is really her own heart now. She creeps closer, her bare feet swishing along the floor.

“T?” she whispers.

“T,” I answer. We always call each other T when we are alone. I close my eyes, a tear falling down my cheek. What have we done?

Painfully, I move over on the bed as best I can. We haven’t just come out of surgery, if the date on the wallscreen is correct. They put us in a medical coma for a few days to speed up healing. I find the fact they can do something like that more than a little frightening. Neither of us has ever been to a hospital before this. There aren’t any in Mana’s Hearth.

Tila slides into the bed. On her chest, in mirror image of mine, is the same wound that will one day become a scar. Beneath her false sternum is another new, false heart. I wonder if they are set to the same rhythm and even now beat together.

Gently, we turn onto our sides, pressing our foreheads together. Then and only then can we fall back asleep, in the position we have fallen asleep in for the last sixteen years. Now three inches of emptiness separate us, when before there had been nothing, and our heart had beat as one.

1. Taema

ONE

TAEMA

Ten years later

I’m starting where it all falls apart.

Tila is late for dinner.

We meet twice a week, once at her place and once at mine, though lately it’s always been at my apartment in Inner Sunset. She says she’s staying late at work, but I never know if that’s true. I hate it when she keeps secrets. It used to be that we couldn’t.

Outside, fat drops of rain drum against the glass window. The sunset has faded to darkness, a few stars just bright enough to shine through the San Francisco fog. I pace across the living room, peering at the blurred view of the city skyline, the green shimmer of the algae farms in the bay, the lights of the hovercars flying past. I paid a lot extra to have the penthouse for this view, but at the moment it does nothing for me. All I can do is be irritated at my sister.