Her house had five windows: one faced the ocean, one the mountains, one the plains, one the sky, and one the ground. The one facing the ground was always dark, but the others changed throughout the day. Her favorite place to sit was in the exact center of the house.

In school, her favorite subject was geometry and their house was a triangular prism.

They’re doing everything with computers now, her father said, but he had arranged the whole house by hand and with a compass.

With a compass and a straight edge, she could draw anything. She drew patterns in her notebook, oblique angles. She could bisect lines, create perfect squares.

Each wall of the prism was a different color meant to reflect light so they needed no lamps. It was an efficient design.

The triangle is… her father started, then he went back to work.

She laid back and looked out the top window at the stars. The window revealed much.

The triangle is… she thought, and she drew a few triangles in her notebook. Her house’s bases were equilateral, for the upright rectangles shared the light best. She drew others, favoring the isosceles.

Outside was the ocean, the mountains, and the plains, and they too formed a triangle. She longed for three arms to stretch out in three ways. She tried to lift one leg and point in three directions.

The door to the house was invisible, but when she pressed three fingers to the right spot, it slid open.

On the floor she tried to fold herself into shapes. She made her body parallel to each wall. The window facing the ground revealed small rocks, dirt, and worms. She watched a worm squiggle between the glass and the earth.

She tried to squiggle and the movements were so irregular. Her father frowned. She went outside and tried to build a third arm from a stick. She tied it around her chest and it stuck out from her sternum like a terrible weapon. She pointed in three directions. Move carefully.