My niece

I live alone, I don't really like those who call themselves family. The only one that keeps me company is my rottweiler.
I had to babysit my niece since she was born. I didn't really give any attention to her until she was 16. Her body blossomed quite well, she has such beauty and her body always makes me hard when I look at her. Sexual scenarios race through my mind every time she visit, I try to stop because she's my niece, it became worse during this summer. She stayed with me for the whole July, she enjoyed my small swimming pool in her tiny bikini. Every morning, I watched her behind my curtain upstairs, she enjoyed being on the side of the pool, relaxing on the long chair. I couldn;t stop staring at her breast and ass, her breast is so big and she choose to wear something that barely cover it.
I kept staring at her with my hard cock in my hand. Warm feeling and excitement ran through me, I had to jerk. My cock spurted semen on the floor while I looked at her. It's so difficult to think about something else because she's my niece, I was wondering if it was fine or very wrong for wanting to fuck my niece, shes family.

One morning, the excitement came to another level. She was on the long chair on the side of the pool. She must have thought she was alone, she took off her small bikini. I bit my finger and tongue. I had the urge to jump on her. She was caressing herself. I wanted to watch a bit longer. She spread her legs and stroked her pussy. She must be horny as I was right now. She's 16 and my niece, it's wrong of me to think she would have someone like me, a 48 years old man. She would think that I am a creep. Somehow it's what I am, I am watching her like an old perv from above with my cock being so hard. I have to take a walk to force myself to remove such thoughts.
I left for a while, but i was still excited when I came back home. I thought I should get a prostitute tonight to calm my urge. But when I came back home, something has happened I would have never expected.
I couldn't see my niece anywhere, she wasn't longer at the pool. I looked around in the house, I couldn't find her. Maybe she's in her bedroom, I discreetly going to her bedroom door, not making sound.
She was there naked on the bed, and what a sight, my dog was there on the bed with her.
My rottweiler' cock was hard and in her mouth. He was on his back, she was on top sucking his cock. Her face said it all, she was loving it. My dog wasn't moving and it looked he was enjoying it greatly. Then I understood something. My dog was disappearing in the night, I thought he was going to drink water from his bowl in the kitchen downstairs or wanting to sleep somewhere cooler. He must have been in her bed because I have heard a noise that wake me up one time. It was like a little bang and some little scream of pleasure. But I didn't hear very well and my foggy mind told me to ignore I was just dreaming.
So it's what they were doing.
I kept watching her, I was enjoying it. She moved to be on her back and my dog moved too. He was just standing above her, his cock on her face and she sucked his cock again. I could hear her pleasure of sucking him. 16 and she's already a bitch.
She moved to be on her hands and knees and offered her pussy to my dog. He licked her pussy and there is no word to describe it, it was very exciting. Little moans of pleasure came out from her little mouth, then the dog mounted her with his paws around her waist. Then her hand drove the dog's cock into her pussy. The dog was bigger than her and looked heavier than her too. His cock went inside her, she breathed hard and deep, then she screamed, she said she can feel his knot now then he pounded her. It was intense to watch. Her big breast kept bouncing forwards and backwards, her body in this position was so exciting to watch. I felt the need to touch myself. I want to fuck her so much too.
I felt more excited when she screamed her head off, the way my dog fucked her was intense. He kept going and going without slowing down. He grunted, I knew what it meant, he was loving it. He had a bitch there to fuck and she wanted it too.
I don't know how long it lasted. Their fucking lasted a while. Then he dismounted her, I could see his sperm dripping out from her pussy. The dog's cock was still hard and she quickly moved to suck his cock again. She licked and swirled her tongue all around, swallowing what was there. It was so hot to watch this. I wondered how my cock would feel if her tongue did the same on mine. Then she said something, I thought she caught me, but there were something else in her bedroom, she was actually live streaming it. She moved to the camera with her open mouth, then she swallowed all, she was telling to the camera how much she loved dogs spunk.
Oh my god, she's really depraved. She must be live streaming it on the dark web since she's under 18 or she could have lied.
Then she said to the camera that next time, she would tied in a kennel and spent the night there surrounded with horny dogs.
I moved away, I needed to release myself. I found her thong in the laundry basket and wrapped it around my hard cock and masturbed until I cum.
Now I wondered how long she was doing this. I have never seen her with a boyfriend and her parents never mentioned one.
Now I know her secret, next time I will film it and show it to her just to blackmail her. I wouldn't show it to her parents if she let me fucking her.