My sister Amber is 5 years older than me. She has brown hair, blue eyes and is about 5'5'. I sneaked a peak at her bra once and she's a 32c. She's very attractive and has had numerous boyfriends. I just graduated from high school and am going to college in the fall. She still lives at home and is on summer vacation as well. We both have jobs where we work nights so we're always home alone during the day. On this particular day, I just could not help myself.
Amber likes to sunbathe out in the backyard. We have a fairly big yard so it's very quarantined back there. My room faces the backyard. I usually have a clear shot looking at her from the first floor. That faithful morning, I woke up late as usual and got on the internet. I was surfing around when I realized hey, I could looking at porn. So I slipped my boxers off and looked at some sites. I'm sitting there slowly stroking my semi-hard boner when I glance up and see Amber laying in the grass outside my window.
I quickly turn the volume down since the window is open. As I look over again, I see that she's in a new bikini that I'd never seen before. She must have just bought it. Anyways, it was very tiny and revealing. I'd never seen anything like that one her before. Her tan, slim body was baking in the sun. I suddenly realized that I was now fully erect so I started pumping away looking at her.
Her eyes are closed but I have no idea if she's awake or not. I move over to my bed to get a better angle. She might have sensed movement because she rolled over onto her belly. The bikini was very tiny so I had a great view of her wonderful ass. All I could picture was me slapping my cock against that ass. I started stroking even faster. I knew this was going to be a good one so I reached in my bottom drawer and pulled out my lube. As I was covering my hard cock with the lube, she untied her bikini top strap.
I risked being seen by getting closer to the window. The lube felt great on my cock and made a little squishy noise. Amber then lifted her head and looked around. She turned over and I swear she looked right in my eyes. I suddenly froze with my hand wrapped around my 7 inch. We must have locked eyes but she suddenly broke away from my gaze. The next thing she did amazed me. Her top came right off. I couldn't take my eyes off her wonderful tits. She laid back down and had a little smile on her face.
Then she closed her eyes again while softly caressing her boobs. One hand slowly slipped down her belly and rested on her bikini bottoms. As she rubbed, I was jerking my cock faster and faster without thinking. My eyes were fixated her this gorgeous sight and then I saw her eyes on my hard cock. Her hand went under the bikini bottom when I stood directly in the window.
'Take the bottoms off,' I whispered. Amber moaned softly and slide them off, revealing her cleanly shaved pussy. She went back to working her sweet pussy. I could feel my orgasm building inside me. 'I'm about to cum,' I said to her. She nodded and mouthed me too. Amber arched her back and squeezed her tits as she moaned to an orgasm in front of me. I waited for her to be looking again when I aimed my cock straight up. My cum erupted all over my chest and belly while some dripped to the floor.
Amber put a finger to her lips, 'Shhhh,' and went back to sunbathing nude. I smiled and took a shower.