A Lady and a Ghost

"Nelson!"

A shrill female voice rang out behind Nelson. He froze for a moment. The voice was somewhat unfamiliar, yet also so familiar.

An unbelievable guess rose in Nelson's mind, one that even he found absurd. He slowly turned his head, his eyes widening more and more as he cried out in disbelief.

Standing behind him were a lady and a ghost.

"Minerva, Professor Binns," Nelson asked, eyes wide and tongue-tied, "why are you..."

"Here, you mean?"

Professor Binns shook his head, took a rust-covered yet still silver-bright pocket watch from his robes, and pressed down hard on the rusted winder.

In an instant, time froze. Only the three of them, enveloped by its power, could still move freely.

"Professor, why have you come to... to Ancient Greece?!"

"You asked me to."

"But I haven't—"

"You will, won't you?"

Professor Binns raised an eyebrow, and a smile bloomed on his face, one Nelson had never seen before. It was like a crossword enthusiast winning the biggest prize the local newspaper had ever offered since its founding, brimming with pride and gratification. It was a smile that should not have appeared on a ghost's face, and it made Professor Binns's soul seem incomparably alive. He had spent his whole life studying the mysteries of history, and that smile seemed to be the reward for his lifelong persistence.

Nelson paused, and a smile appeared on his face as well. At that moment, the two historians of magic were smiling with equal happiness.

"How did you get here?"

"With... this thing." McGonagall gently pointed at the pocket watch swinging in Professor Binns's hand. Her eyes struggled for a moment, and she swallowed many things back down. "The Time-Turner. This is your invention, isn't it?"

"Where did you find it?" Nelson frowned. "I swear,