Sometimes portraits moved from one painting to another, as if traveling between them.
They occasionally helped the living deliver messages, but that only referred to the portraits in the headmaster's office. A portrait like Bloody Baron's beside the Potions classroom did not take on that task.
When Pomona arrived at the Slytherin dungeons, she happened to encounter Bloody Baron in his ghostly state. He floated past her expressionlessly, just like Grey Lady had when Pomona encountered her in the Divination classroom last time.
Phineas Black was the most unpopular headmaster in Hogwarts history. There had been other Slytherin headmasters before him, but he...
The Potions classroom door suddenly opened, and Severus stood in the doorway.
"How long are you going to stand around here like an idiot?" he asked viciously.
"I was thinking about what happened in 1984," she said dazedly, as if under the Imperius Curse. "One of your 'friends' infiltrated Hogwarts."
He did not dwell on the matter of "friend" for long and simply walked past her toward the exit.
"Where are you going?" Pomona asked.
"To eat," he said coldly and mercilessly.
"Wait!" Pomona jogged after him. "How about we have a picnic?"
"I have other things to do," he said, still icy.
"When we investigated Harry Potter's Expecto Patronum last time, we got a 'T,'" Pomona said, refusing to let up. "I still need to go to Ravenclaw Tower to find Flitwick. Wait for me!"
Without waiting for his reply, she ran up the Grand Staircase.
In 1984, the first school year after they returned from XZ, a Death Eater had infiltrated the school. By some unknown means, he trapped a Muggle-born Hufflepuff girl inside a painting. Bill Weasley had still been attending school then. Like Hermione now, he was Flitwick's prized pupil. The difference was