"Ah, Evelyn, do you need something?"
"Yes, Professor Lupin. I received a suspicious letter, and I wanted to check if there was a curse on it. After trying, I found none, but I would still like a professional's opinion to make sure I'm not falling into a trap."
"Oh? And why do you think the letter is suspicious?"
"A big black dog gave it to me."
He seemed shocked before taking the letter I handed him without saying anything.
After casting a few spells, he opened the letter and read it, frowning.
"It seems you're just the victim of a prank."
"How so?"
"The letter contains only these words: 'I hope you stressed out thinking it was trapped.'"
"That's really not nice… And why a black dog?"
"I can't say, but this person is quite clever."
Of course, this letter was from Sirius, a way for him to contact Lupin.
Few hours ago,
I had finally placed the anti-magic chains that appeared when I requested them in the Room of Requirement.
Once I was sure he could no longer transform into an Animagus or escape, I de-petrified him.
"Where am I, and who are you?"
"You say hello when you're polite, Sirius. Just so you know, you can't escape, and it would be better if you cooperated and answered my questions."
"Are you going to turn me in?"
I saw a hint of regret and resignation in his eyes.
"Not necessarily. You see, from the beginning, your incrimination has seemed very suspicious. Although all the pieces fit together to form a picture, I'm certain it's not the right one. For example, why did you escape from Azkaban only now, when you could have done so long ago, given that there was no evidence of a previous escape attempt?"
Since the beginning of the year, this lack of answers has haunted me, making me wonder what really happened.
I thought I saw a glimmer of hope in his eyes.
"The only thing I want is for you to tell me the whole story about what happened."
He told me that he had been friends with James Potter, Peter Pettigrew, and Remus Lupin, and that they had eventually figured out that Professor Lupin was a werewolf.
For several years, they worked to become Animagi, so they could keep Professor Lupin company during full moon nights, as werewolves do not attack other animals.
They were living in a rather dark period because of Voldy. One day, he made plans to kill Harry, who had just been born, so his parents decided to protect him with the Fidelius Charm.
And finally, the answer to all my questions was revealed—Sirius had never been the Secret Keeper.
It had all been a trap to lure Voldy, as he knew about Sirius's close connection to James.
The real Secret Keeper was actually Pettigrew, who turned out to be a traitor.
After confirming that Harry was safe, Sirius went to chase Pettigrew. When he caught him, he publicly accused him of betraying James and Lily before Pettigrew blew up the street and ran away.
Sirius was arrested and never received a trial due to the chaos in the department at that time.
If only they had given him Veritaserum, he would never have been sent to prison.
He escaped from Azkaban after seeing a picture in The Daily Prophet, which he obtained during a visit from Minister Fudge. The picture showed Peter, who had taken refuge in his Animagus form in a wizarding family.
Peter could turn into a rat—and he was the Weasley family's pet rat.
Sirius recognized him because he was missing two fingers. After showing me the newspaper picture, I could only agree that Ron's rat was the real culprit.