Hades pushed me through the mirror after explaining only a few things.

1. I could either observe from the human's point of view, take on my own form (while only being visible to the human), or take over their body. I can do any of this whenever I want.
2. Don't use powers to harm humans.
3. Try to learn as much as I can.

Then he sent me off. I felt as though my mind was melting and being put back together, and suddenly I was standing in the center of a summoning circle. I looked around to see five people sitting on the outside of the circle, all wearing hoodies. My eyes were instinctively drawn to a girl. She had a pale, sunburnt face, blue eyes, and short red hair. This was the girl I had to possess, wasn't it? But a boy with tan skin and black hair spoke up, "Demon, what is your name?" Oh, this was some kind of cult. Cool. "My name, mortal, is incomprehensible for your ears to behold." I said firmly, making all of them inch back a little bit. I cracked a smile. "I'm kidding, my name is Regina. Why have you summoned me?" I knew I was just supposed to possess the girl, but I wanted to hear the reason here. "What can we do to prove your existence, to stop people from calling us crazy for knowing the truth?" He asked me. "Nothing," I stated, "There is nothing you can do to prove our existence.. Now to do what I truly came here for." I said, confusing everyone around the circle. I turned towards the girl. "What is your name?" I asked her. "I-It's Julia.." She said, trying to not sound scared. I smiled and walked closer. "I'm not going to hurt you. Erase part of this circle." I knew this specific summoning circle also acted as a container. I had no powers in it. "Julia, don't!" One of the other guys exclaimed. Julia ignored them, and rubbed away part of the black chalk on the ground. I kneeled down and tilted her face so our eyes met. I felt myself shift places, now entering her mind as a separate entity.

"Julia.. Are you okay?" I turned to see that a girl with blonde hair and brown eyes had asked the question. "Well, let's just say that Julia has a roommate." I said, smiling. "You possessed her!? Let my sister go!" The blonde exclaimed standing up. I stood up as well. "Calm down, she's still here, I'm just currently at the controls. She can do anything she wants." "So.. I'm possessed?" I heard her ask. "Yes, you are. You can still be in control at any time, I just wanted to set some things straight with your friends here." Julia didn't say anything about that, so I assumed it was fine to keep speaking. "I'll be here with Julia, learning about humans and their society. I'll leave eventually." I explained. The people looked at eachother, then at the black haired boy. I assume he's their leader. "You swear you won't hurt anyone?" He questioned, narrowing his eyes. "I swear." I said, holding out my hands. "Then.. Is Julia okay with it?" He added. I let Julia answer for herself. "Yeah, I'm fine. She isn't really hurting anyone, and he just wants to know more about humans." She said through our now shared body. Our voices had different tones, so it was clear who was speaking. "Well then I guess its settled.. Regina stays." The blonde, Julia's sister, said.