Conditioned Response

Maddie kept replaying the scenes over and over in her mind, since she had not recorded them. She kept getting aroused when she pictured that thick shaft bucking and pulsing, and the subsequent thick streams of cum. She really could not help but wonder how it must taste.

Wednesday was another very long day on campus for Maddie. When she got off the bus Thursday afternoon, she hurried to the house as soon as she saw Todd's car in the driveway. She was still breathing heavily when she turned on the camera and leaned forward expectantly in her seat. Jasmine was not there this time. Todd was lying back in his bed. He had removed his pants and underwear, and he was stroking his erection.

Maddie adjusted the camera, centering her brother's cock on the screen and zooming in. Her hand once again slipped into her panties, and she was staring at her brother's dick with her mouth open and watering. She did not realize what she was doing to herself, when the word 'delicious' ran through her head again and again. She shivered through an intense orgasm, and then she moaned helplessly when she watched her brother's cock buck and pulse. Look at all that yummy, creamy sperm! she thought as she watched it shoot out in a geyser to land on Todd's abdomen.

That night, Maddie lay awake in her bed for a long time. She could not get the image of Todd's hard cock out of her mind. As she pictured it, she brought her hand to her face and her lips closed on her thumb. As soon as she started to suck on her thumb, a shot of arousal coursed through her pussy. She writhed on her bed as she sucked her thumb and stroked her pussy through her panties. The entire time, she was imagining sucking Todd's hard cock.

After three embarrassingly intense orgasms, she finally fell asleep still nursing on her thumb. No one bothered to wake her up the next morning, and she slept in. It was a disruption of her normal regimented schedule, and she felt groggy when she finally woke up and started her day. Maddie had very little school work that Friday, and her fatigue put her in mind of some sleep study data she had run across a couple years earlier. She had no recollection of sucking her thumb the night before, but she vaguely recalled bucking pleasurably against her fingers.

She fired up her computer and began looking for those sleep studies. She never did find the original studies she had read, but there was a mountain of information from hundreds of recent sleep studies available online. Her attention was arrested by some interesting tidbits about REM sleep. She spent several hours poring over those results, until she realized that she had missed lunch.

Maddie felt terribly irresponsible as she strode to the kitchen to fix a late lunch. She hadn't even had breakfast! She was even more annoyed with herself when Todd and Jasmine came in the front door. It felt like she had wasted the entire day.

"Hey, Maddie," Todd said, but his voice trailed off. Maddie turned to find her brother and his girlfriend staring at her. She looked down self-consciously and realized that she was still wearing the clothes she had slept in—just a snug t-shirt and panties. Her nipples were obvious little mounds against that tight cotton, resting on the swell of her breasts. It wasn't as if the shirt was see-through, and it did cover the tops of her thighs.

After Todd and Jasmine had shaken off whatever that was and went into Todd's bedroom, Maddie cleaned up her lunch dishes and went to her bathroom. "Oh, no," she said softly when she saw her reflection. Her normally neat, combed hair was disheveled. It hung around her face in unruly rivulets. She wasn't even wearing her glasses. She shook her head in disapproval, but then suddenly stopped and stared at her reflection.

Wait a second, she thought. I actually look...good! For once, I don't look like such a geek.

Unfortunately, she really needed her glasses to see. She thought it over while she was in the shower. Perhaps she could convince her parents to let her get laser eye surgery. It was fairly inexpensive, and the procedure has become far more standard and safe in recent years. She did the math quickly in her head. The corrective surgery would cost about as much as five or six pairs of glasses. It was an argument she expected to win easily.

She went from the shower to her bedroom with the towel still wrapped around her. Sitting at the computer desk, she began to organize her thoughts. She wanted to prepare her presentation thoroughly for her parents before she bothered to approach them. She stared at her computer screen as her mind worked. Abruptly, she gave a little hop in her seat when she realized that Todd and Jasmine had gone into his room some time ago.

As long as she was just organizing her thoughts, she could see what they were up to...

The window opened on her screen at the very end of that blowjob. The camera was still zoomed in closely as Todd's cock bucked upward into Jasmine's mouth. Maddie could not see her brother's hand holding her head down, or the sharp look Jasmine gave him. Her thighs spread of their own accord, and her hand found her sensitive clit just in time for her to stimulate that little button while she watched the base of Todd's shaft pulse. She could hear Jasmine gulping loudly as she swallowed, and that set her off instantly.

Maddie was leaning forward once again, drinking in that sight and shaking as she came. She's swallowing every drop of my brother's delicious sperm! she thought.

When she realized that was what she was thinking, she guiltily turned off the camera. She missed what came next—Jasmine pulling her mouth off of Todd's spent dick and spluttering, "What the hell, Todd?" She was not happy about the way he had held her head down and face-fucked her. He hadn't even asked before he shot his cum down her throat.

"Sorry," Todd breathed, but his expression told a different story. He looked deeply satisfied, and not the least bit sorry. Jasmine slapped him hard on his shoulder and then pulled up her panties and shorts.

"You're an asshole!" she spat before marching angrily out of the house.

Maddie was deep into her presentation on the benefits of laser eye surgery, unaware that her brother had just suddenly become single.

* * *

The next day Maddie was up earlier than her brother, once again tuning in for a marathon session of Dr. Who. Todd had far less interest in the series than Maddie did, but he was familiar with the premise and most of the characters. He was eating a bowl of cereal on the couch next to her, until their mother called out, "Todd! You know better than that. No eating in the living room!"

He groaned and got up, returning to the dining room. Maddie had to catch her breath. When her brother had stood up, she realized that he was not wearing anything under those thin grey shorts. The outline of his thick cock had been clearly visible, only a foot from her face. It was something she had never noticed before, but he often went commando when he was just hanging out at home.

Once again, it struck her as being unfair. She was wearing her uncomfortable brassiere at that very moment. Her mother called out from the front door, "We'll be gone until late this evening. You can call your dad's cell phone if there's an emergency."

It was the same thing she said—verbatim—every time they went out, Maddie realized. She wasn't being thoughtful; it was just something she was used to saying. She paused the show and got up, suddenly annoyed. Todd gave her a glance as she walked past him and into her bedroom. She closed the door and took off the shirt and the bra. She got a clean, fluffy sweat shirt from her closet and put it on, gently rubbing her breasts through the shirt.

Oh, that felt so much better. It wasn't even obvious that she wasn't wearing anything under the sweat shirt. Still, she felt a little guilty thrill when she walked past her brother. It was the first time in five years she had been around anyone without one of those constrictive bras. She returned to the couch and resumed watching her show.

Todd finished his cereal and rinsed out the bowl before rejoining his sister on the couch. Maddie felt her sensitive nipples harden beneath that sweat shirt. She could not help but glance over at her brother's lap as he lounged on the couch with his legs splayed out in front of him. With his legs spread like that, the thin material was drawn snugly over his crotch, and the outline of his shaft and bulbous head were easily visible.

Maddie gulped and forced her eyes back to the television screen. Every time Todd shifted next to her, though, her eyes were drawn back to his cock. She swallowed repeatedly, and was not consciously aware that her mouth was watering.

Two more episodes passed and then Maddie's attention was once more drawn to her brother lounging next to her. He had started to snore. She paused the television once again and looked at him carefully. His pupils were moving back and forth beneath his eyelids. Clearly he was deep in REM sleep already. Maddie had her feet drawn up underneath her legs, and she turned on the couch to look at her brother as he slept.

"Todd?" she said softly.

He had no reaction. She looked down at his lap again, and sucked in a breath. His cock was noticeably thicker and longer now. As she leaned forward for a closer look, she was shifting her legs. Unaware that she was even doing it, she was mimicking Jasmine's position as she knelt with her face closing in on her brother's lap. Her mouth was watering and her pussy was damp. She felt light-headed when her nostrils caught that first whiff of her brother's masculine scent.

She was dizzy, not thinking clearly at all when her shaking hand reached out and touched her brother's warm thigh. His only reaction came from directly in front of her face. That thick shaft pulsed and grew at her light touch. Maddie was breathing heavily, constantly swallowing her saliva as her mouth watered. Her hand slid up to the bottom of Todd's shorts, and she gently pulled the cloth upward.

Maddie moaned softly when the head of her brother's cock came into view. It was just inches in front of her. She could feel the heat emanating from him. Her hand pushed the hem of his shorts higher, and the head of her brother's cock rose. It slipped easily between her lips. She moaned softly around that fleshy knob, savoring the texture and taste of it. The tip of her tongue explored the slit at the end, and she got her first taste of his salty-sweet pre-cum.

Her eyes shot open when she realized what she was doing. Oh my god! she thought. She pulled her mouth off of him quickly, and pulled his shorts back down to cover his hardness. Maddie was shaking as she sat back, unable to believe what she had just done. She shifted uncomfortably, and then had another shock. My panties are soaked!

Her legs were shaking unsteadily as she got up from the couch, retreating to her room. She dropped her shorts and panties and then stared at the massive wet patch. Her trembling fingers found her soaking-wet pussy and her eyes rolled up in her head. Her mouth watered as she re-lived that amazing sensation of her brother's throbbing cock head in her mouth. Even though it had only been a fleeting moment, she could still taste him. She shuddered and came again.

What is wrong with me? she wondered as she pulled on a fresh pair of panties.

By the time she returned to the couch, Todd was waking up. He stretched and smiled at her before getting up to use the bathroom he shared with their parents. After he returned, Maddie noticed that he was no longer hard at all. She swallowed her disappointment and returned her attention to the show.

When that episode ended and the next one began, Todd turned to her. "Maddie, would you mind if we watch something else for a while? I'm pretty sure that we've seen this episode at least twice."

"Okay," she replied, handing him the remote. It wasn't an unreasonable request.

Todd tended to switch channels often when he had the remote. Maddie was used to it, so it didn't annoy her when he did it. He found two shows that he liked and would switch over during the commercial breaks. Neither of the shows interested her, but at least they weren't awful. She was a little preoccupied. The taste of her brother's cock was fading from her mouth.

She did not even realize that she was staring at his cock again until she heard him call her name. "Maddie? Are you okay?" he asked.

He was concerned at the vacant stare she had on her face. It never occurred to him that she was staring at his dick. She looked a little flushed, and he worried that she might be sick.

"Sorry!" she blurted. She realized that her brother just looked worried about her. He hadn't caught her staring. "Maybe I should get some lunch," she said after thinking for a moment.

Todd glanced at his watch, then stood up. "That's a good idea," he said. "I hadn't realized it was already after noon."

They went to the kitchen and began fixing lunch. Maddie was uncomfortably aware of the prominent bulge in her brother's thin shorts, as well as how inflamed her aroused nipples felt. She looked at the clock on the microwave and turned to her brother.

"Isn't Jasmine going to come over?" she asked.

Todd blew out an exasperated breath. "I don't think you'll be seeing her anymore," he replied.

"What do you mean?" Maddie stuttered out. Had Todd found out that she had been watching them?

Todd wasn't looking at her when he sadly shook his head. "I...did something stupid and pissed her off. I tried to call and apologize, but she won't answer her phone. I left a message saying I was sorry, twice, but she hasn't called back. I'm afraid it's over between us."

"Oh," Maddie said. She was so relieved that it didn't occur to her to ask what her brother had done. It never would have crossed her mind that the very act that she had witnessed the previous day had been that "something stupid."

After she washed down her first bite of her sandwich with a sip of soda, Maddie realized that there was not a trace left in her mouth of her brother's cock. Earlier, when it had happened, she had been shocked. She couldn't believe she had done it. Now...she wished she had kept him in her mouth just a little longer. A lively internal debate was raging in her mind while she mechanically chewed and swallowed her lunch. Todd looked over at her a few times as he ate his lunch, wondering what she was thinking.

He had seen his sister lost in thought like this many times. On those occasions when he asked what she was thinking, she would let him in on her thought process. Half the time, though, those topics were out of his intellectual league. She had not been reading comic books today, so he figured it was another of those incomprehensible physics debates that she was having with herself. He decided not to ask.

After lunch, Maddie returned to her room. She wanted to clear her head of the image that was stuck there—she could not stop picturing her brother's fat, swollen cock head right in front of her face. She figured that if she worked on her project to convince her parents to let her get laser eye surgery, it would help her clear her mind. To an extent it was working.

She went over the outline, from the benefit analysis to the cost analysis to the risk analysis. She felt like she was missing something. She sat back in her chair, tapping her closed sharpie marker against her lips as she thought. She was not even aware of it when her lips closed on the rounded tip of the marker and she began pushing the tip in and out of her mouth.

Her eyes shot open, and she pulled the marker from her lips. "Oh! Insurance!" she blurted out. She leaned forward and began rattling away on her keyboard as she looked up their insurance coverage and explanation of benefits. She sat back in her office chair, blinking, when she saw that coverage. The insurance would pay for her laser eye surgery. She would only have to cover the $50 co-pay for each eye.

Excitedly, she popped her thumb into her mouth. She was looking at the screen as her mouth hungrily slurped on her thumb. This would bring the cost down to less than what she paid for her last pair of glasses! There was an audible "pop" as she pulled her hand from her face, copying the insurance information into her outline. She could not wait for her parents to get home so she could tell them about this!

* * *

That night, Maddie stood in the living room with a look of stunned disbelief on her face. "What?" she asked.

"I said 'no'," her father repeated. Maddie looked to her mother, who was also shaking her head.

"But...it's only a hundred dollars," she said. She felt numb. "I have earned that much allowance money. It won't affect our insurance..." All of that had been in her presentation. She was flailing inside, unable to fathom her parents' response.

"Maddie, clearly this decision has nothing to do with your eyesight. It's about vanity," her father said. "You've worn glasses your whole life, and now all of a sudden you want to do this. It is just an attempt to make yourself more appealing for some guy, and it is sickening. You don't have to do this. Any guy who is that shallow doesn't deserve you."

Maddie was shocked into silence. Her face reddened and her mouth hung open. She and her parents turned their heads when Todd spoke up.

"Come on, Dad, that's just ridiculous," Todd said. He actually looked upset. "Maddie has never in her life been vain. What she is asking for makes perfect sense, but you guys are being completely unreasonable."

"That's enough!" their father snapped. "We told you 'no' and that's it! I don't want to hear one more word about this."

Maddie's hands shook as she closed her laptop. She continued to stare at her parents for several more seconds before she turned and stumbled to her room. Before she could close her door, though, she heard her brother speak up. She had only heard him angry a couple of times before, but it was clear in his voice now.

"Dad, that's crap," he said. Todd was clearly struggling to keep from shouting. "Maddie has been a model daughter her entire life. She has never questioned you, she's obeyed every one of your rules, she's never been in trouble, and she's gotten straight-As since junior high. If you're going to be this unfair, I'll pay for her eye surgery myself."

"Todd!" their mother gasped.

"You should take two days to think it over," he said, his fists still clenched at his sides. "If you can't see that you're being completely unfair, and that Maddie is right, then you don't deserve her respect."

Maddie stood in shocked silence and watched her brother march into his room, slamming the door behind him. She quietly closed her own door. The last thing she saw before that door closed was her parents' stunned faces. Her legs were shaky as she set down her laptop and plopped down in her bed. She was grateful to her brother for sticking up for her like that. She just worried that it would get them into trouble with her parents.

* * *

The next morning, Maddie woke up gradually. She realized that her thumb was in her mouth. She pulled it out and looked at it curiously. It glistened with her saliva. That's odd, she thought. I've never sucked my thumb before.

She didn't think about it again after she had gotten out of bed and gone to the bathroom. She dropped her sweatpants and panties, rising to pull her sweatshirt over her head before she dropped it on top of the other clothes. After her shower, with a towel wrapped around her, she brushed her hair back and tied it up in her customary bun. She picked up her discarded clothing and carried it to her room, dropping it into her laundry basket as she always did. In the process, she never noticed just how damp her panties were.