The Wrath of the Witch

On October 24, there was a murder. A boy at the local high school was somehow stabbed to death without anyone noticing. It's surprising how stuff like that happens these days. Everyone's too busy looking at their phones, they never notice anything around them.
October 25, a woman was hanged. The authorities don't know whether it was a suicide or a murder. According to her friends and family, her mental state was perfectly fine. She had never attempted suicide or hurt herself, so nobody has a clue on why she might've killed herself. But after looking at the evidence, I got the answer to that question. She didn't kill herself at all. She was murdered!
On October 27, there was a huge house fire down the street from the woman who was murdered on the 25th. Four people died. It was at 3:52 AM, long after all four people went to bed. The fire couldn't have been started by anyone inside the house. That narrows it down to two options: Someone outside the house accidentally set the house on fire, which is unlikely, or someone purposefully set the house on fire. Which means, it's murder.
A total of six people have died this week, and I need to find whoever is committing these horrendous crimes.
---
This morning was so successful! Four more dazzling human souls have been added to my collection! I feel so bad about the boy a few days ago, though, because he was actually really cute- but witches can't date humans! I have a hard time following that rule, but I have to or else I'll lose my powers- for good this time!
Today is October 31, which is a super special day for us "paranormal entities" as the humans call us! It's Halloween, the greatest day of the year! I get to go out and expose myself to the humans! I get to drop that "innocent girl" personality and be myself! I get to choose who goes into my collection and who I leave for for the others to devour! Ahh, I love watching others suffer! It's my favorite feeling in the whole world!
---
I'm hiding in an alleyway, shivering. A high school girl, Carol, I think her name was, was huddled behind a dark building, talking to three big, intimidating men and a woman. She didn't looked scared, not in the slightest. Her activity lately has been quite suspicious!
---
Oh my goodness! She's slowly walking over to me holding some sort of staff... Maybe it's just a Halloween costume... If it is, she sure doing a great job with it!
"Oh, look who we have here," she grinned devilishly and stood before me, her eyes twinkling. "I'm glad you could join me today."
After that last part, I completely blacked out.
---
That stupid agent almost caught us doing our Halloween dirty work! I can't believe he saw us! What a cheater! As punishment, I'm going to extract his soul early... I was planning to do it after Halloween, to create a diversion for when I murder someone... Important... What the humans call their "president." He's so gullible...

I tie the agent up in my unbreakable ropes... Made from the finest spider silk. Nothing can break that stuff!
He tries to struggle, but that gets him nowhere. Obviously. I grab his shoulders and begin to claw at his chest. After I got most of the skin off, I take my soul powder and sprinkle some on. Not too much, not too little. Just right. The purple and blue substance slowly trickles into my ectoplasmic jar, the ghostly liquid trapping his gorgeous soul within its boundaries.

Happy Halloween, agent boy.
---
Happy Halloween, you monster.