I had to start fully trust Anna

All mondays are hard. But that one was particularly difficult. I was horny all the time. I would have had the biggest hardon of my life, if it hadn’t been for that chastity lock. In addition to the kinky daydreams I was constantly putting diving in, I had received a picture from my sister just before the break, taken in her bedroom. She was fully clothed, showing a small anal plug just out of her bag. An annotation was saying “it was this morning. it’s waiting for you, go and get it now”. When the bell rang, I rushed home by foot, my school being fairly near from it. When I closed the front door behind me, I received another picture where she was still clothed, but bent forward just a bit, almost showing a nipple. Her free hand was behind her back, lifting her skirt a bit. She was clearly inserting the plug in her ass. “I did it first, now it’s your turn. Open the next image when you put it.”

The house was empty. I went to Anna’s room and found the plug on her night table. It was a large black-tinted steel diamond plug. I felt the phone vibration in my pocket. I grabbed the plug, undid my pants, and got on all four on the bed. I was so turned on that my ass opened itself easily under the jeweled toy. I felt a strange sense of satisfaction, as if having something penetrating me was for me an equal way of getting off. That was it, I thought. My sister’s goal was to make me addicted to anal sex. I was again in that dilemma. Enjoying her manipulation and dominance, but fearing it at the same time.

I opened the last picture. The plug was on the night table, Anna’s tongue letting her saliva drip onto it. “Now you have to wear it for the whole day. If you just put it before coming home, I will see your ass is not stretched enough and you will wear it tomorrow too.”

That was so hot. I was frantically rubbing my cage, my nipples, and playing with the toy in my ass. Did it mean I was going to get fucked tonight? By her with a strapon? Or was she planning to have someone else do it? Or just me and a dildo, maybe?

I spent my classes just thinking about my naked sister’s breasts. Round, perfect, covered in oil. I would have been so happy if she had just wanted to fuck me with a strapon. Just that would be so wonderful.

When I came home, I had to bear the whole evening, watching the news, eating with the parents… When the night finally came, Anna came to my room. She had had lingerie in her hand. For me.

“Hey put this on, Selina. We’re gonna go somewhere to be alone tonight. Just the two of us. And I want you pretty.”

I would have said yes to anything. I put on the corsage, panties and thighs. On top of that, I had a long dark blue dress and high heels. I felt very feminine when I put those on. Everything suited me perfectly.

I just followed Anna without any questions. We drove a few minutes to a house I didn’t recognize.

“Mike is on holiday with his parents. They gave me the key so I would come check if everything was alright. Which means we have the whole place for us this week!”

We went in, she lead us to the upper floor and stopped just before a door. She turned around and handed a blindfold.

“Now you will have to trust me for the rest of the night, baby sister. Because you will not use your eyes once.”

I put on the blindfold, and it all went pitch black. I couldn’t see anything through, nor by the bottom like you could hope with that kind of fabric. My sister lead me inside and made me kneel somewhere around the center of the room, I think. She sat on something in front of me.

“Okay sissy. Are you horny?”

“... Yes…”

“Have been wearing your ass plug all day like I told you? Show me.”

I turned around, lifting my dress while rising my ass in the air. I moved aside the string of my panties to show off the beautiful plug I was wearing. I was proud to prove my submission. At that moment, I wondered if there wasn’t anyone else in the room watching.

“Good girl… Now take it off.” Anna said as a command. I obeyed, and I could feel that my ass was behaving like she wanted to. Spread wide for anything to come in. “Perfect, sissy.” she added before sliding a huge dildo inside me in a swift motion. I let out a moan of contentment. “You’re eager for that, right, slut? And you’d love getting fucked by a real cock, right?”

“Oh yes I’d love it!”

“Sit on that dildo and ride it like it was the cock of your man.”

The dildo had a solid base to hold in place while I was fucking myself on it. As I was just beginning, Anna handcuffed my hands together in my back. That was so hot. My heart was racing, my cock struggling to come out. More than ever I was feeling the reality of anal pleasure. What I had been doing for my blog - stuffing my ass with a dildo and jerking off at the same time - was uncomparable to this. Not being able to masturbate was forcing me to find the pleasure where I could. With my ass. My sister was really turning me into an ass slut. But she also could tell how good I was feeling. After a few minutes riding the dildo like a cock craving whore, she stopped me.

“You behaved well, Selina. We’re leaving now.”

Now? I was so close. And I couldn’t just stand up and go outside now. I was too overwhelmed by the experience. I felt a hand grab me and make me stand, then come out the room. I heard the door close before Anna took away my blindfold and my handcuffs. I barely managed to go down the stairs in my long dress, dangerously balancing on my high heels. I wasn’t happy with this outcome. Which made my surprise even bigger when we got home, and my sister told me I could touch her breasts.

We were in her room, standing right next to her bed. The dim light was shaping her smooth curves and outlining her pointy nipples. If I could have had a boner… I groped without restraint the pair of magnificent C cups. Anna was acting like she didn’t feel anything and was just manipulating me knowing I still wouldn’t cum tonight. But I noticed a few times she was taking a long, deep breath that my touch wasn’t leaving her unaffected. She let me fondle her for two minutes before sending me to my room. I went to bed wondering if she was masturbating right after.