For ten years, that rusty gear has been in the inner pocket of my suit. At the class reunion, Siting asked me softly if I had any news about her. My fingertips became cold. The sight of her rushing into the rain on graduation day, and the unsolved mechanics problem in front of the blackboard, never let me go. It wasn't until I pushed open the classroom door and saw her standing in the light covered in dust that I realized that some answers would take three people ten years to calculate together.
