For a time, homeless people could be seen everywhere on the streets. Once, Pomona noticed that there seemed to be fewer of them, but she had not paid much attention to it. It was not until the First Wizarding War ended and Severus came to Hogwarts that she learned those vagrants had not gone elsewhere.
No one cared when they disappeared. The Dark Lord understood that very well, so he sent people to seize those helpless souls. It seemed he had intended, like Grindelwald, to build an army of Inferi.
The difference was that Grindelwald had sought the Resurrection Stone, while the Dark Lord had been more interested in the Philosopher's Stone. But he had died too suddenly, and no one knew where his army was.
Now they knew. But discussing such a topic over a meal was far too appetite-killing, so Pomona changed the subject.
"Grosseteste once said that light was the 'first form,' and possessed materiality, while matter must necessarily spread into a three-dimensional world," she said as she chewed her food. "Is that the principle behind the Dark Lord using a spectrum to resurrect himself?"
Severus quietly chewed his food, maintaining impeccable table manners.
"About Nicolas Flamel," Pomona said after swallowing a mouthful. "Flitwick thinks the fire demon he sealed was a mental projection of Grindelwald. Perhaps he saw it somewhere, and then the fire demon took on its appearance."
"Didn't you say you were thinking about space and time?"
"Isn't this what I'm talking about? A dimensionless form cannot increase or decrease from the day it comes into being, while light multiplies. So it cannot be the second form. What do you think a dimensionless existence is?" Pomona asked.
"Imagination?" he asked.
"Are you asking me or answering me?" Pomona asked.
He thought for a while,