The first swap came after the big fight about your job. You rolled to my side at 3 a.m., not to be closer, but to feel the dent my body had made—as if sleeping in my absence might help you understand me. I woke up on your side, smelling your shampoo on the pillow. We didn't apologize. We just stayed swapped for a week, learning each other's angle of the ceiling fan, each other's patch of morning sun.