After speaking, he closed his wallet.
"So in your wallet, there's a Snake Monster and a Sphinx?" Sebastian whistled awkwardly: "You're much cooler now than I was back then, Harry. I'm glad I taught you so many fun spells."
"Yes, and then you got locked up in Azkaban." Harry sighed, "How are you feeling now? I'll get you out soon—once I ask Moffin Gaunt where Omnius's portrait is."
"Yes, you mentioned Omnius earlier. What did his letter say?" Sebastian asked, concerned.
"Omnius said he used Time Magic to seal Annie in a cave, hoping that a hundred years later there might be a way to break the Black Magic Curse." Harry replied.
Upon hearing Harry's words, Sebastian seemed stunned.
His cloudy eyes stared blankly at Harry, seemingly unable to believe what Harry had just said.
"What's wrong?" Harry asked with concern.
Unexpectedly, Sebastian held his head in pain, grasping his sparse hair, saying in a low voice, "Merlin... Omnius... Omnius..."
He sobbed quietly, unable to regain his composure for a long time.
Harry sat beside him, staying until he spoke again.
"This magic... I know this magic requires the caster to pay with life." Sebastian said painfully: "Those who fool with time will ultimately pay some sort of price... Omnius..."
Harry was shocked as he looked at Sebastian, never expecting that freezing Annie in time would require such a hefty price.
"I shouldn't have entrusted Annie to Omnius, I knew, I knew..."
Sebastian reproachfully pounded his head, loving his sister dearly yet unwilling to sacrifice his best friend because of her.
Seeing his sorrow, Harry comforted him: "Perhaps it's not as bad as it seems, you know, Omnius always finds a way."
When Sebastian remained indifferent, wallowing in his sadness, Harry encouraged him again: "Maybe you should come out with me, together we'll look for Omnius and rescue Annie."
"It's useless, Harry." Sebastian said softly, "I'm a wanted criminal by the Ministry of Magic; they won't release me easily."
"I'll go to Dumbledore," Harry told Sebastian: "Dumbledore is the president of the International Wizarding Union; if he intervenes, I'm sure you'll be out soon."
Sebastian raised his head.
"If it's just to get me out, that's not difficult." Sebastian said quietly: "Actually—"
He finished speaking and stood up.
Harry was horrified to find that Sebastian's previously aged body collapsed like shedding skin, and what stood up was a transparent ghost.
Still in his seventeen-year-old appearance, frozen in time as it were in Harry's memory.
"I stole this Dark Magic Item from Omnius's home, which allows me to disguise and evade Dementor searches—actually, I died decades ago."
Harry found it hard to accept.
"But clearly you just..."
Sebastian laughed indifferently: "I told you, it's Dark Magic, don't inquire too much about Dark Magic—don't worry, Harry, I won't teach you this magic, I fear Grindelwald and Malfoy might come to settle scores, utterly wiping out my ghostly body."
"They won't." Harry quickly asserted, then curiously asked after observing Sebastian's ghostly form: "How do I get you out? If those Dementors see you, they'd latch onto you, trying to drain you dry."
"Open your wallet, I'll jump in temporarily." Sebastian advised, "Then release me when you return to Hogwarts—goodness, you know how much I miss Hogwarts life?"
Sebastian's voice was casual, as if it wasn't him who had become a ghost.
Harry could only comply, opening the wallet, Sebastian's ghost swiftly jumped inside.
He pocketed the wallet, took a last glance at Sebastian's body, then turned to leave the cell.
Just as he stepped out, Dumbledore emerged from Moffin's cell, gesturing to Harry as he saw him.
"Looks like you've finished chatting with Mr. Saru?" Dumbledore asked, "How was meeting an old friend?"
"We'll talk after we return." Harry replied to Dumbledore.
Dumbledore suddenly asked seriously, "Did you put him in your wallet? I must remind you, Dementors can't detect him in your Traceless Stretching Spell pocket, but they will inspect the original cell."
Harry understood Professor Dumbledore's message.
What he took it to mean was: if you plan to take him out, I think you should hide him in that Traceless Stretching Spell pocket of yours and find a suitable replacement, otherwise the Dementors will give you trouble.
"Something small happened, he turned into a ghost." Harry said quietly: "He said he died long ago, but because of some small Dark Magic Items from the Gaunt family, he remained undetected by Dementors, and if they discover he's a ghost, it might not end well for him."