Nasir and Keiko are in a room with a single window. The window is on the wall to Nasir's right. He is facing away from the window toward the wall on the opposite side of the room, meaning the window is behind him. Keiko is facing Nasir. There's a bird outside that flies past the window. Who sees the bird?

Make your response very short.
Keiko can see the bird fly past the window. Since Nasir is facing away from the window and it's behind him, he cannot see the bird without turning around. Keiko is facing Nasir, and therefore, is also facing the window behind him. Her line of sight includes Nasir and the window, allowing her to see the bird as it flies by.