In a universe where shadows have physical mass and can interact with their environment, Zephyr and Shanika are standing in a field with a single light source directly overhead. Zephyr's shadow cast by the light is touching Shanika's feet. If Zephyr waves their hand, how does Shanika perceive the movement, given that shadows have physical mass? Respond very briefly.
Since shadows in this universe have physical mass, Zephyr's hand waving would cause their shadow to also move. This movement would transfer through the shadow to wherever it's cast, in this case, Shanika's feet. Shanika would feel a corresponding sensation at her feet, similar to a light touch or brush, which is the shadow of Zephyr's hand moving across her feet. As Zephyr continues to wave their hand, Shanika would continue to feel this sensation on her feet as long as the shadows are touching and she is within the area affected by the moving shadow.