I (22F) let my sister’s boyfriend finger me by the pool [MF]

It was a hot day, so we headed down to the apartment pool. Just me, my 19-year-old little sister, and her boyfriend Matt. I don't have a boyfriend right now, so I figured I would just hang out with them and maybe tease Matt a little more. I couldn't stop thinking about how his cock felt in my hand that night on the couch giving him a quick handjob.

I wore this tiny white bikini I have had forever but never worn. The kind that turns almost completely see-through the second it gets wet. I had never had the guts to wear it before, but with no one else around the pool it felt right. Not something I would wear to the beach since people would think I'm a total slut. But I figured for the apartment pool it was okay.

We all spent some time in the water, and when I got out my bikini was completely see-through. My nipples were fully visible through the soaked fabric. It clung to my curves and left nothing to the imagination. The bottoms hugged my pussy so tightly it looked like I wasn't even wearing anything. I caught Matt sneaking glances more than once, especially at my ass when I slowly bent over next to him to grab my towel. I sat down to dry off and spread my legs just enough to let him look.

After a while, my sister went back upstairs to shower and grab some drinks and snacks. The second she was gone, I laid back on one of the lounge chairs and gave Matt a look.

"Hey," I said in my sluttiest voice. "Can you rub some sunscreen on me? I need your hands on my back."

He came over, and squirted some lotion into his hands and started rubbing my shoulders. I jiggled my hips slowly while he touched me.

"Lower please." I whispered.

His hands slid down my back, rubbing it, and I moaned, "A little lower" I said again. Matt's hands went onto my ass and started rubbing it. His fingers gripped both my ass cheeks like he couldn't help himself. He looked nervous, almost guilty, but he didn't stop. His touch lingered gently, then he gave my ass a firmer squeeze. My stomach fluttered, and I let out a soft moan. I shifted my hips, pushing back into his hands just slightly. Then I spread my legs wider, giving him a clear view of how the thong disappeared between my cheeks, tight against my pussy, and already wet from more than just the pool.

Then I rolled over and gave him a flirty smile. My tits bounced slightly, and the bikini top clung tight to my nipples.

"Can you please do me now?" I said, "I mean do my front too?"

He didn't say a word. He squirted more lotion into his hands and started rubbing slow circles across my stomach. The lotion slicked my skin, turning into wetness under his touch. I let my legs fall open and watched his eyes drop. The bottoms were stretched tight against my pussy and the fabric was doing nothing to hide how turned on I was.

I bit my lip and looked up at him.

"Lower please."

He froze. Then slowly moved his hand down between my thighs. I grabbed his wrist and guided him under my bikini bottoms. He felt how wet I was, and his whole body tensed. His breath caught in his throat. I whispered, "It's okay. She's gone. Just keep going."

He started rubbing slow circles over my clit, my pussy so wet it slicked his fingers with every move. I was fucking drenched. I could feel the heat building in my stomach and my pussy was already throbbing hard, like it was screaming for him to play with me more. I spread my legs wider and pulled the fabric aside to let him have full access to my bare pussy. My clit was swollen, tingling like crazy under his touch. He slipped one finger inside me then another, stretching me just right, filling me so good I grinded against his hand. His fingers moved slow and deep, hitting spots that made my eyes roll back. I whispered, "Fuck, don't stop" my voice all shaky, hips bucking to take him deeper.

He looked down at me, face flushed, breathing hard, his cock bulging so hard in his shorts it looked painful. He was tense, like he wanted to stop but couldn't, his eyes glued to my dripping pussy, like he was losing it. He kept checking the gate and glancing at the building, scared my sister would catch us, but he kept fingering me.

I clenched around his fingers and came hard. My legs shook so bad I nearly screamed. My pussy gripped his fingers, pulsing tight as my whole body lit up. My clit throbbed so hard I couldn't think. I gushed cum all over his fingers. He kept his fingers deep, slowly twisting them as I rode it out. My moans slipped out louder, not giving a shit who heard. I came all over his hand. My pussy still twitched like it wanted more.

When he pulled out, his fingers were drenched, glistening with my cum. I was still buzzing, my pussy throbbing, wanting to keep him there forever. I grabbed his hand and took one of his fingers into my mouth.

"Thank you. I should return the favor someday." I whispered, sucking his finger slow. "I have some techniques you might really like."

He looked like he was going to cum in his shorts. A few minutes later my sister came back with drinks and snacks. Matt acted like nothing was wrong and I smiled all relaxed after an amazing orgasm.

Later that night I played with myself again thinking about how Matt touched me. His fingers still felt inside me, making me wet all over again. I'll have to get some more alone time with him.