Brother Cums in Sister's Bikini

Grayson sat up on his bed, sunlight streaming in from his window. He reached for his buzzing phone and switched off his 10:00 AM alarm. Excited, he crawled up to his window and slowly peeked over the ledge. By the pool was his younger sister, Amaya, sunbathing on her back in a black bikini. Their backyard was surrounded by tall fence that kept any prying eyes out which Grayson was eternally grateful for as it led to Amaya sunbathing everyday for the past week, right at 10 AM. She was back from her first year at college, freshly 19, while Grayson had already graduated at 24. She had cycled through all her bikinis, from a green one with strings wrapping around her body to a red one that disappeared into her bubble butt. However, the black one she was wearing today made his eyes pop. The bottoms were fairly modest, but the top was a push up that smushed her C cup tits together. He lowered his boxers and grasped onto his morning wood with his already lotioned up hand.

Their parents had left for a two week cruise to Mexico and the same day Amaya was out there by the pool, soaking up the sun. On the first day, Grayson just took a peek every now and then, a little afraid to get caught. But by the fourth day he was unabashedly stroking his cock, too horny to care. She was always facing away from his window which allowed him to stare all he wanted. His favorite part was when she turned over and untied the strings on her back, her cute butt and naked back on display. He noticed Amaya pick up her phone and a couple seconds later his phone lit up with a text from her.

"Can you pleaseeeee grab me a lemonade from the fridge?"

A little peeved at the interruption, he quickly put his boxers back on and threw on a pair of shorts and shirt, tucking his boner into his waistband and headed down the stairs, hoping it wouldn't be noticeable by the time he got outside. Trying to avoid openly looking at his sister, he walked towards her looking at the sky with the lemonade stretched out.

"Here you go Amaya"

"Thank youuu", she replied, absent mindedly reaching out her hand without looking and made contact with Grayson's bulge, still a little chubby from his session earlier.

Grayson jumped at the touch, spilling a little bit of lemonade, but he was more surprised that Amaya had no reaction to it. Thinking that there was no way she didn't notice what she just touched, he walked back inside and decided to start making breakfast like he usually did. He thought it would be too suspicious to stay in his room with his sister already knowing he was up.

As he was setting a stack of pancakes on the table, Amaya rushed back inside and yelled,

"I forgot that I was meeting Kiera at the mall today, I'm late!"

Grayson yelled back a reply but was more focused on her ass, jiggling as she bounded up the stairs. His erection started to come back and planned on using the time she was gone to finish what he started in his room.

After finishing his pancakes and seeing Amaya rush out in a tight pair of jean shorts and a yellow crop top that showed off ample cleavage and toned midriff, Grayson waited a couple minutes to make sure she wasn't coming back. He was walking back to his room when he noticed Amaya's bedroom door open and the black bikini he just saw her in laying there.

"She must've been in too much of a hurry to put it away" he thought, growing harder as he went to pick them up. He held the bottoms with two hands and gingerly sniffed at it, smelling a slightly sweet and musky aroma. Overcome by his horniness, he brought up the part where her pussy would've been up to his nose and deeply inhaled. Though the smell wasn't too strong as she had barely worn it, his cock was rock hard at the thought of where these had been just thirty minutes ago. He wrapped it around his member, the tip touching where he just smelled and started stroking, his other hand reaching for the top. He smelled that too, though there was even less smell coming from it. He grabbed the bikini cups and imagined he was grabbing onto Amaya's tits, softly pinching where her nipples would be. The image of his sister in the morning came to mind and he could feel an urge coming from his balls. He was so turned on that he lasted much less time than normal. Still in the hallway without the tissue box that was next to his bed and not wanting to have to clean the carpet, he held the bikini cup in front of his cock and stroked faster.

"Oh fuck"

He spasmed a little as white gobs of cum shot from this cock into the bikini top, groaning in pleasure as he filled it up. Despite it being a C-cup bikini, his sperm was almost overflowing and he had to be careful walking it to the bathroom to clean. Washing his sister's bikini in his post nut clarity haze made him feel a little ashamed, but figured as long she never found out then it would just be his own innocent little thing. After wringing out the water, he put the bikini back as he found it in her room.

About to leave, he noticed her drawers open and glanced inside the top one. Panties of all colors greeted his eyes and his deflated cock gave a little twitch. He gingerly picked a pair up and spread it out. It was just a regular pair of pink cotton panties, but it still got his rod to start to perk up. Giving it a quick sniff, he decided to come back for them another time, when he was fully recharged.

Next Day

Grayson woke up again to his ringing alarm, excited to see what color his sister was wearing today. He poked his head up the window and was surprised to find Amaya facing the house now instead of her usual spot near the deep end looking towards the fence. He quickly ducked back down, afraid to get caught peeping. Instead, he put on his swim trunks and headed out to the pool.

"Cannonball!"

Watching Amaya in the same black bikini she wore yesterday, he jumped in and aimed his cannon ball splash at her. As he surfaced he could hear her yell at him for getting her wet and got a pinecone thrown his way for his efforts. He was smiling, both from getting her splashed and having an excuse to stare at her bouncing titties as she was threw the cone.

"Aren't you going burn being out here so often?" Grayson asked his sister.

"Oh! Thanks for reminding me, can you put suntan on my back? I can never reach and I'd like to even out my tan."

He hesitantly nodded, worrying about the half chub he had in his pants at the moment, slowly growing at the thought of seeing her up close. He awkwardly walked towards her and grabbed the sunscreen as she turned over. Making sure she wasn't looking, he snuck a peek at her ass, absolutely gorgeous up close. Her legs were closed so he couldn't see in between, but his eyes were on the bikini bottoms anyways, remembering how they were wrapped around his cock just a day ago. He shook his head and started spreading the sunscreen, getting harder and harder as he was rubbing it in. He was almost ready to cum once he was finished with her back.

"All good?" He asked.

"Yep, thanks Grayson!"

He quickly jumped back into the pool and swam in order to get his boner to die down, but by the time Amaya went back in, he was still sporting a steel pole underwater. Knowing that his sister always showered right after, he waiting a few minutes and followed her upstairs. The gap at the bottom of the door was unusually large in their house, so he was able to get his phone underneath and tried to snap a few pictures, emboldened by his horniness. He took a look and though there was some steam, he finally laid eyes on his naked sister, able to see a glimpse of nipple in one picture and a little bit of her pussy in another. He ran back to his room and began furiously jacking off, zooming in the pictures onto Amaya's nipples. His session lasted even less than the one yesterday and soon he was holding a tissue in front of his cock and cumming buckets into it. Grayson cleaned himself up and once he was soft again, he went back into the hallway looking for more, hoping to catch Amaya coming out in a towel. Like he imagined, she came out in a slightly too small towel and almost ran into him.

"Oh hey, should we order pizza tonight? Watch a movie? I'm think I'm too tired to cook."

"No problem Amaya, I'll order some from Luigi's later then. Same order as always?"

She nodded and walked into her room while Grayson bent down and tried to catch a glimpse of her pussy again.

Grayson found himself peeping at his sister again later that night. They had opened a bottle of wine with the pizza and put on The Notebook while eating. Grayson was so distracted they could've put on any movie and he wouldn't have cared. Amaya was in fleece short shorts and a tank top in which he could clearly see she was not wearing a bra. He saw the small indents of her nipples whenever he glanced down and caught many eyefuls of sideboob. At the moment, Amaya was sleeping on the couch next to him as wine always made her a little sleepy. Grayson tried to listen to her breathing to make sure she was asleep before he made a move. He moved the top over so that her nipple was uncovered, meticulously checking her eyes to make sure she stayed asleep. He took a couple pictures and then moved it back. What was more exciting was that he couldn't see her panties underneath her shorts, which either meant she wasn't wearing any, or they were very small. He carefully moved the shorts aside, and uncovered a seemingly perfect pussy, almost making him instantly cream his pants. He couldn't believe what he was seeing, after only getting a low quality picture of her in the shower, he got to look at her tits and pussy up close. It was the hardest he could every remember getting. After taking a couple more shots, he moved it back, afraid of getting caught. He covered her with a blanket, turned everything off, and headed upstairs to masturbate. With the up close and personal look he got, it didn't take long for him to nut and he quickly fell asleep after, still thinking about his sister.

Next Day

Waking up the next day, he started his morning routine. But when he poked his head up, Amaya was nowhere to be found.

"Looking for me?"

Grayson whipped around to find his sister emerging from his closet, clad in only the black bikini he'd been fantasizing about. He tried to stammer out a reply, but she cut him off.

"You didn't clean this very well. Imagine my surprise when I came back to find white streaks in one of the cups. Also could you be any more obvious in the window? Right as I sat down I could see you in my phone."

"S-sorry Amaya," he said back, taking note of her smirk. "You're not mad?"

"A little. I didn't mind you peeking when I was tanning. And after feeling your bulge made me rethink what I was going to do. Combine that with the fact I haven't got any action in a while... well I decided to just go with the most convenient thing. Hence what I was, or more like what I wasn't wearing yesterday. Look, you're just a dildo to me, got it? My own personal sex toy, nothing more. "

Grayson nodded, not believing what he was hearing. His cock was ready for action though, straining against his boxers. Amaya laid him back down on his bed, stripping off both their bottoms and grasping her own in her hands.

"I'm guessing this is what you did?" she asked as she positioned them over his cock.

He moaned as he felt her hand wrapped around him. Waves of pleasure washed over him as she started stroking, getting faster and faster until she suddenly released her grasp. She reached behind and untied her top, pulling it over her head. She stuffed it in his face and stepped onto the bed, slowly lowering herself on him. Her titties were the perfect handful, with nipples on the smaller side. He reached up to pinch her nipples, hearing her moan when he did.

She reached down and rubbed his cock against her pussy lips, lowering herself until the tip popped in. Amaya moaned as he first entered and dropped herself until he was all the way in. Grayson couldn't believe the feeling of his sister's pussy, unbelievably tight and he could feel her wetness already seeping onto his pubes. One of his hands were on her hips while the other was keeping her bikini up to his face. He watched her tits bouncing, still in disbelief that he was fucking his sister.

"Ohh fuck Grayson" she moaned, occasionally tweaking her nipple. "You feel so fucking good".

He listened to her moaning and the slapping sounds of their bodies meeting, feeling the urge start to build up in him. They quickly got into a rhythm with Grayson thrusting hard into her. His hand roamed her body as they were fucking, feeling her smooth, tan skin. She leaned down to give him a kiss while he was still inside her. Feeling her tongue exploring his mouth, he started thrusting faster and faster.

"Fuck sis, where do I finish?"

She started slamming down even harder once she heard that.

"Inside, I'm on the pill"

Hearing that brought Grayson over the edge, he took a deep whiff of the top as he felt himself cum. He grabbed her hip to slow her bouncing as it was starting to get too sensitive for him. He groaned, feeling that her walls were tightening and sucking all the cum out of him. After pumping everything out, Grayson looked up at his sister to find her pouting.

"My dildo hasn't done a very good job of pleasuring me, I haven't even cum and it thinks it's done its job."

"Sorry Amaya, what can I do?"

She got off and laid back on his bed next to him. Grabbing his hand and bringing it to her pussy.

"How about you rub your cum all over me?"

He began to massage her lips. He made sure he paid special attention to her clit, remembering his ex's lessons on pleasuring her.

"Wow, big brother is good at this."

Grayson could feel Amaya squirm more as she was nearing her orgasm. He sped up, feeling his slick cum on her lips.

"Ohh" she moaned as she came, Grayson feeling her shake and slowed down. They both laid there, out of breath in a post orgasmic bliss.

"I think were going to have a lot more fun before mom and dad come back."