Sister dropping her bra (pre story)

My name is Marc. I’m 18 years old and live at home with my parents and my two older sisters. My sisters are Margot and Sofia and they’re 23 and 21. So I’m the youngest in my family.

“Marc?” Sofia said, when she came down to my room.
She’s not afraid of interrupting me to ask if I want to do something, but I usually also just have my door open so it’s fine.
“What” I replied.
She stepped into my room with a lotion in her hand. I could see she had been showering. She had a towel on her head and she was wearing nothing but her underwear. Her bra was a skin-toned and had matching tight fitted knickers. She exercised a lot and was in an unarguably good shape. I knew she looked good. Even my friends told me I had a hot sister.
“You think you could help me with my back?” she asked, while unscrewing the lid of the lotion. I paused the YouTube video I was watching and stood up without answering. She walked to her room and I followed. She opened up her bra and held onto it with her hands cupping her breast. I put some lotion on my hands and started rubbing it out on her skin. I got it down to the bottom of back and touched the top of her nickers. I dragged my hands up along the sides of her and felt the curvature of her body. I have to admit that what I felt was nice. I dragged my hands down along her sides to “ensure” that I spread the lotion well. As I did she jumped a little. I knew she was very ticklish.
“Did that tickle?” I teased her.
“Stop!” She responded with a voice that tried to be angry.
I knew she wasn’t really mad, but just hated to be tickled. I then grabbed her on her sides with my hands doing a tickling motion. She was shocked and tried to stop me. She pushed my hands of her sides with HER HANDS. Everything happened so quickly that I almost didn’t realize that her bra was now laying on the floor. Even though she still faced the back to me. I’m not gonna lie, I saw some boob. Only really the side of one but it was enough to make my dick to grow a little. Not noticeable, but I could definitely feel it waking up. She quickly grabbed her bra and placed it on her boobs again.
“I am so sorry! I didn’t mean to do that!” I said. It was true, I actually didn’t mean to make her drop her bra.
“It’s okay” she said and turned around. She revealed her very red and embraced face.
“I didn’t see anything” I assured her, to calm her down.
“But I think I’m done with the lotion” I said and turned around to leave the room. I felt like leaving now. Also because I could feel my dick getting harder the more I thought about what I saw. It was also the only thing I could think about.

We were a little more distant that day than we used to be. Two days had now passed and everything were back to normal. I was walking down the hallway to get to my room. I passed Sofia’s room and I saw her sitting on her bed texting (like usually). I changed my mind and chose to join her. I sat in one of two chairs bought for when she wanna move out.
“What are you on about? Are you going to take off my panties this time?” she asked teasing me.
“I said I didn’t mean to make you drop it!” I insisted.
“Did you see them… my boobs?” she asked.
“No, I mean I didn’t see much” I said.
“Did you see them or not” she laughed a little.
“I didn’t see them then” I said. Now I was the one feeling embarrassed and I don’t even know why.
“If you’ve already seen a little you might as well just see them for real.” She said deadly serious.
My heart actually skipped a beat. I wouldn’t believe my own ears. I’m sure she also saw my mouth dropping a bit.
She stood up and walked over to her door to close it. I starred with an unchanged face and followed every of her movements. She pulled her t-shirt over her head and smiled at me. I think she enjoyed showing her tits to her brother. She was wearing a black bra today, but not for long. She got close to me and turned around.
“Undo it! It feels a lot better when it’s somebody else undoing it” she insisted. She grabbed her bra on her boobs. I did as she said and undid it. She turned around, and with a smile on her face she let go! I could now see everything. They were beautiful and round. I could tell she enjoyed the attention.
“You wanna feel them?” she asked, and without an answer she grabbed my wrists and brought my hands up on her boobs. I grabbed them. They were amazing. They felt even softer than they looked. She stepped back and went.
“Now you’ve seen my boobs, it’s only fair I see your dick!” I can’t describe how hard my dick got when she said that. She pulled me up from the chair and said “Now we change roles” she laughed and I enjoyed every second of this! She left her boobs uncovered.
“Strip!” she commanded me. I did as told at pulled down my pants. I knew she found out my dick was hard now when I stood up and had no pants on. Her cheeks got red. I slowly pulled down my underwear to the point where my dick bounced up and stood straight out in the air. Without asking she just went down on her knees to rub my dick. I enjoyed the sight of my sis sitting on her knees, topless playing with my hard dick. I looked up for a little while to enjoy her dick-massage. Suddenly I felt a little gab folding around the tip of my dick. By the time I looked down, she had my dick down her throat. She started a back and forth going motion. At this point I was so close to cumming. I warned her. “I’m gonna cum” I said. She kept on sucking. I tried again. “I’m gonna cum in your mouth” I tried. She sped up and I looked her in her eyes. She knew what she wanted! I then released the warm cum into her mouth. As I stopped cumming she pulled her head from my dick and showed me her cum filled mouth while she swallowed. I don’t know if I’ve ever seen her this happy!
When she was done swallowing she stood up. She dragged her boobs up my body and pressed them onto my chest. She whispered in my ear. “Come to my room 3 a clock tonight, I want you to eat my pussy!”

This was a pre story I therfor definitely plan on releasing the main story soon. Please feel free to tell me what to do better, this is my first time releasing a sex-story

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