A/N: This is a short story requested by four-el4.
*****
She has a nice ass was the first thing Dylan thought as he stared at his sister.
It had only been a few days since he came back home from college for the break. Being able to relax after all those exams was pretty great. Well, not the exam part. What he hadn't expected to see was his sister. For one thing, she was also in school. For another, they were both still in school, but they went to different ones. While he opted for college, she went to a university. Some would argue that they were basically the same thing. It really didn't matter. What mattered was that he didn't think she was on the same schedule as he was and that he wouldn't see her during any of his breaks.
Not that it was a bad thing. Heck, he figured they got along pretty well compared to other siblings. Then again, neither of them looked like they were related. His fur was red and hers was white. She also happened to have blonde hair. Most would assume that they were friends or maybe lovers. It's happened before and they would laugh it off and explain they were brother and sister.
Well, he was certain brothers don't check out their sisters. It was weird, but it was kind of hard not to stare when he realized how much of a female she was. The loose t-shirt that went over her bra covered breasts. Tight pants where he can't tell if they were leggings or yoga pants and that show off her hips and ass. Her ass was what got him the most. Compared to her average breasts - they were not small or big - her ass was practically calling out to be touched and used.
Staring at her ass move and bop up and down, he can see her neon blue string thong slightly rise above and then sink into her pants. It was not on just one side either, but on both sides of her ass in a strange symmetrical way. He has seen plenty of asses, yet his sister's took the cake. There were plenty of girls to check out back at the college so he would know.
There was this wolf girl with huge knockers. They practically bounced with every step she took and all the guys would stare at her chest. She just smirked, knowing what effect she had on the male population. Her butt, however, didn't match up to his standards. Seeing the purple thong peeking out of her jeans, he could make out an image on it. Right away, he could tell it was one of those sports thongs and the image was some kind of mascot.
Then there was the tiger girl in his math class. She was unbelievably shy with almost no breasts and a small butt. Basically, she was the classic nerd. He had been surprised to see she was brave enough to wear a black, lacy thong. The only reason he noticed was because she had gotten on her knees to pick up the books she dropped when she had bumped into someone. He remembered staring dumbfounded as how her sweatshirt had rode up while her sweatpants had slid down so he could get a glimpse of her thong.
His favorite girl happened to be a cat. Instead of pants, she loved to wear dresses. Sometimes, with a dress, it was harder to appreciate a girl's butt. They made a girl's hips and waist stand out, and maybe the breasts, but the booty got no appreciation. Fortunately, this wasn't the case. She loved the ones that wrapped around her figure in a vice grip which made every curve stand out. It was even better when she took to wearing really short ones where you could basically see her thong as she walked. It was practically a red string. Nothing was left to the imagination. Most of the guys bet she already slept with more than half the guys on campus.
Yet he found himself unable to tear away from Cassandra's ass. He had never thought about her wearing a thong. It was one of those things that siblings never thought about or talked about. Well, he was certainly thinking about it now. What other colors did she have? Did she perhaps lacy ones or maybe a spots one? Just thinking about the kinds of thongs she would wear got him excited.
As she moved past him, she glanced away from her phone to give him a slight smile before going back to texting.
The thought she might realize he was getting hard thinking about her, specifically her ass, and the possibility he might give into the temptation were enough to send him packing. Acting as if nothing was out of the ordinary, he headed back to his room and locked the door behind him. He collapsed onto the bed, trying to block the image only to fail. With a growl, he kicked off his pants, revealing his hard cock. Closing his eyes, he wrapped a hand around it. He was no longer in his bedroom. Instead, he was with his sister in the living room.
His hands trailed along his sister's fine ass that's in his lap. She turned her head to give him a coy smile before grinding her ass into his cock. Feeling the pants rubbing against his cock and watching as the thong shifted around her hips, he groaned. He fingered her thong, feeling the fabric. It felt soft to touch and he wondered what if would be like around his cock. Unable to resist her teasing ways, he grabbed her by the hips and humped her ass. She moaned and moved in sync with his movements. It was too much and he came over her ass and thong.
When he opened his eyes, he saw that his stomach and lower half were covered in his seed. His hand was sticky as he sat up to find tissues. They were unfortunately on his table and he nearly tripped over his pants that clung around his ankles. Cleaning up the mess he made, he zipped up his pants.
At the sound of a door closing, he stared out his window. The silhouette of his sister moving away from the house meant it had been the front door and she was probably would be gone for the night. He would be home alone. That meant he could do whatever he wanted without getting caught. He knew exactly what he was going to do with the time and headed for his sister's room. Dylan couldn't remember the last time he had been in his sister's room. Maybe he had never been in there.
The first thing he noticed after flipping the lights on in the dark room was the bookshelf. Taking a book out, he saw it was a biochemistry book and a quick glance at the other books told him they were physics and biology among them. On the floor was a mat for Pilates. It looked recently used, probably just before she left. None of those interested him though. His goal was her drawers and after looking through several, he found her panty drawer.
It was a party in there. From plain to rainbow colored, he could see a wide variety of panties and bras. He chuckled when he noticed a couple stitched with cartoony images. To think Cassandra was into that kind of thing. He had never pegged his sister to be into those kinds of things considering how in love she was with her science textbooks. Picking a few to get a better look and feel for them, he made sure to put them back carefully. Dylan didn't want her to be suspicious. The last pair he found himself holding was a red micro thong.
Instantly, his mind returned to the fantasy he had earlier, but instead of the neon blue thong and black pants, it was the red one above a pair of white yoga pants. After licking the panties slightly, he pulled his pants down before settling down into her chair. His hands wrapped the red micro thong around his shaft and began to jerk himself off. Perhaps it was because he was still sensitive from earlier or the fact he was actually holding, no, using his sister's thong to get off, but he soon came.
A quick inspection assured him that his cum hadn't stained it, but when he took a closer look, he realized he could see small holes. Parts of the microfiber had been slightly torn from the friction. There was nothing he could do. He placed it back into the drawer, hoping it wasn't too ruined or noticeable. What were the chances of her picking them to wear any time soon anyway. She might not even notice until weeks later. For now, he cleaned up any possible evidence of his trespassing.
Just as he finished tidying up, he heard a door open. It could only be the front door which meant she was home. How long had he been in her room? It couldn't have possibly been that long. Whatever the reason, he needed to get out of there and fast.
Rushing to turns off the lights, he carefully shut the door. While he would have preferred heading to his room, it would be too obvious that he had been up to something. She would wonder what he had been doing so his only choice was to go down the stairs. He met his sister halfway. His heart nearly skipped a beat when he realized how close it had been. Not only that, but the fantasy was still clear in his mind and seeing her in person so soon made it hard for him to pretend he hadn't imagined fucking her.
