Chemistry Girl

Note: Everyone in this story is 18 years old and above. This story contains incest between brother and sister, so if it makes you uncomfortable then please find another story.

*

The bus ride home was as usual for the most part; Lisa could feel a tingling sensation throughout her body from the moment she left the school doors to when she boarded the bus. Taking a seat in the sparsely occupied public transport while her mind was distracted, she placed her backpack next to her and looked out the window to her left as the doors to the bus closed, and it rumbled on its way. She could still feel the sting from the cut on her hand as she leaned back on the cushioned seat and mentally kicked herself. What would Mr. Thompkins think of her now that she broke a test tube containing the blue liquid?

'He would probably think I'm careless,' Lisa thought, sighing before she rubbed her face with her left, uninjured, hand, 'fuck! He probably thinks I'm a klutz.' While her hands rested on top of each other on her knee-length skirt, Lisa's thoughts turned to the apology she needed to make the next day. After all, she had three weeks with Thompkins before the summer break. Shaking her head, Lisa made a silent vow to not make another mistake with the chemicals or the equipment. As the world outside the bus sped past, Lisa continued to feel this tingling sensation throughout her body. And now, she felt sweat gathering on her forehead, even though the air conditioning in the bus kept the interior cool and comfortable despite the outside heat. She wiped the gathered sweat with her left hand and then stared at the clear liquid before wiping it off onto her red and blue blouse.

Suddenly, Lisa felt as if she was being watched. She looked up from her hand to the short-haired man four rows in front of her. He was not staring at her, but he seemed to turn his head from one side to the next as if searching for something. Lisa then glanced at the older woman sitting on the other side of the bus; she seemed to be in her late fifties and had started to cough slightly before she turned her head towards the short-haired man. Lisa could see the older woman's eyes narrowing at the man, her lips parting slightly, and her tongue licking her lips before suddenly shaking her head. The older woman then turned her head back to the bus window to her left. Lisa was so distracted by the events of the day when she boarded the bus minutes earlier that she could not remember if there were people behind her.

Her heart was racing at the thought that someone from behind her—a complete stranger—was watching her for an unknown reason. She enjoyed having people look at her, but this time there was unease. Lisa could feel more sweat gathering on her forehead and on the back and sides of her neck; she could feel beads of her sweat tracing down her cheeks and nose. While putting the sensation of being watched to one side, she quickly grabbed a Kleenex from her backpack and wiped the clear liquid off her face, neck, and the parts of her chest that were exposed to the air before the top of her blouse could be stained by the sweat. It was when she wiped her chest, just above the top edge of the blouse, that she noticed her arms were covered in a thin film of sweat, as if she had been running for several minutes. With a confused expression, Lisa wiped the sweat off her arms. As she wiped off the sweat off her arms, she swore she could just make out waves rising off her arms; it was as if she was staring at waves of heat rising off roads or pavements during very hot days.

Shaking her head, Lisa attributed whatever she had seen to a trick of the light. She put the Kleenex back into her backpack, but she could already feel herself sweating once again. Lisa made sure the man in front of her and the older woman weren't staring in her direction when she pulled the top of her blouse away from her skin and stared down at her sweat-covered chest underneath the blouse; her cleavage was slick with sweat, as was the rest of her chest. She saw that the inside of her blouse was already stained with sweat, and it was only a matter of time before it seeped through to the outside of her blouse. The only part unaffected was where her bra covered her breasts.

Suddenly, once again, there was the sensation of being watched. It seemed closer now, as if someone was about to touch her. Lisa released the top of her blouse and watched as it crumpled back onto her slick skin. She then turned her head over her left shoulder; she was about to demand to know why she was being watched. However, after she turned her head and body around on her seat, her eyes widened upon realising there was no one there. The bus was empty except for her, the two other passengers, and the driver. Blinking her eyes as she turned back towards the front, Lisa caught sight of the man in front looking back at her with a gentle smile. Lisa smiled back at him before looking away, just before hearing the older woman call out to her from her seat.

"Are you alright?"

Lisa turned her head towards the older woman and nodded her head. "Yes, thanks."

"You look exhausted," the man said, his voice gentle and his blue eyes fixed on her. But there was something about his expression on his face; it was as if he was eyeing her like a predator. She had seen that look before on some of the football players. It was as if he wanted her then and there. Lisa could see how his eyes lingered on her face; his lips parted, but no words came out.

Lisa smiled slightly and said, "I had a long day; I just can't wait to get home."

"You live nearby?" the older woman asked. Lisa turned her head towards the woman and realised she was getting the same expression from her as well. A longing stare, parted lips being licked by her tongue, a look of desire etched on her face.

Lisa could tell there was something weird going on. She had no proof of it, but something felt a little off. She continued to wipe her sweat off her face and forehead while the two were staring at her. Lisa then noticed that the front of her blouse was darker than usual, which meant her sweat seeped through her blouse. The only lightly coloured section of her blouse was over her bra. She shifted her legs slightly, and it was then that she felt her skirt peeling slowly off her thighs and the insides of her wet thighs slipping past each other.

"No," Lisa said before turning towards the man who got up off his seat and was walking down the aisle towards her. "Ummm..." She had to admit that the man had a ruggedly handsome look, especially with the loose shirt and jeans he was wearing. Lisa then noticed the woman also getting up off her seat and walking towards her behind the man. The man sat on the seat just in front of her, and the woman sat on the seat just next to her; their bodies turned towards her.

"Look at you, poor thing," the woman said, her blonde hair tied into a bun and her brown eyes staring at Lisa. The latter could only watch as the woman placed a hand on her left thigh. Lisa then looked up in surprise when the man placed a hand on her right cheek.

Lisa sat completely still, a feeling of shock running through her body as the tingling sensation increased. Lisa then felt the man's fingers gingerly trace down her cheeks while she glanced at the woman, staring longingly at her breasts and gently squeezing her thigh at the same time. Lisa gulped, fear gripping her heart, as the man's fingers reached her chin before he reached back. Lisa watched as he licked the sweat off his fingers—the very sweat that had been on her cheek. She then looked down at the woman's hand, slowly caressing the length of her thigh.

"You look so tired, sweetheart," the woman said, as her chest rose and fell beneath her red blouse. "Come and relax over at my place, and..."

"No," the man said before Lisa looked up at him. He was staring right into her eyes as he continued, "My place is closer. We'll..."

Before he could continue speaking, Lisa finally got her wits around her, grabbed her backpack, and swiftly and forcefully moved the woman's hand off her thigh. Lisa got up from her seat while the man and woman were asking her to stay so that the two of them could find a way to help her relax. But Lisa rushed past them and went to the driver before asking him to stop the bus and let her out. She didn't want to cause any trouble; she just needed to get off the bus. It would take a little longer to reach home on foot—nearly twenty minutes—but she had enough weirdness for one day. She would rather deal with the heat outside than stay on the bus. The driver turned his head towards Lisa, and she immediately caught sight of his eyes staring her body up and down. She watched the corner of his lips curl up into a smile that put her on edge. Lisa turned her head towards the man and woman walking towards her, desire etched into their faces.

"I'm not interested in whatever this weird thing is you two are playing at."

Lisa watched as the both of them stopped with frowns on their faces before taking a seat on either side of the aisle. They still had an expression of intense desire: 'I like it when people want me, but this is taking it to an entirely creepy level.' She then turned towards the driver and asked him, "Please just stop and let me out." No matter what, Lisa needed to get out of the bus. She knew in her very being that she needed to leave.

"Fine," the driver sighed before stopping the bus on the side of the road. She looked back at the door opening before turning towards the driver, who said, "I can get those clowns off of the bus, and then you and I can get some drinks. And we'll see where it goes from there." Lisa simply shook her head; she didn't smile or joke with the driver; she caught sight of his name on the licence and memorised it before turning around and then leaving the bus with her backpack. Once on the pavement, Lisa turned and watched as the bus doors closed. As it drove off, Lisa watched the man and the woman passengers staring at her through the window.

Lisa then began walking the twenty minutes to her home, where she would be able to end this strange day. As she continued onwards, Lisa continuously wiped the sweat off her face and neck until the Kleenex's in her bag were all used up. Her blouse felt slightly heavy because of the sweat it absorbed, and the tingling sensation going through her body now felt as if her whole body was experiencing an intense bout of pins-and-needles. She couldn't help but sometimes chuckle as she continued walking, sometimes stopping to ease the effects of the pins and needles, and then continuing once again. It would be nearly thirty minutes later, thanks to several strangers she passed along the way who desired to stop and speak with her, that Lisa reached the driveway to her cosy home.

The tingling sensations had decreased considerably. Her body felt cooler after wiping off the sweat on her face over the past few minutes. Now she needed a shower to get rid of the sweat on her body, to wash her hair plastered onto her scalp, and then to order something for dinner with her brother. Getting into the house, Lisa dropped the keys into the key bowl on the shoe cabinet next to the front door. After closing the front door, Lisa called out, "Mark! You home?!?" Lisa didn't want her brother to see her looking as if she walked into the house after getting wet in a thunderstorm.

As Lisa rushed up the stairs, she did not hear her brother reply. 'I guess he hasn't come home from work yet.' Lisa went into her room, closed the door behind her, and then put away her backpack. She immediately peeled the wet blouse off her body before throwing it into the laundry hamper. The blouse was followed by her damp skirt, then her bra and her panties. Lisa stared at the reflection of her naked body on the full-length mirror in her room. She could not help but recall the events of the day once again, from the broken test tube to the events on the bus. The latter was the most unusual event she had ever experienced.

"This is the end of one weird, very weird, day," Lisa whispered before she stepped out of her room with a towel in her hand. With her brother still not home from work, Lisa didn't mind walking naked down the hall to the washroom she and her brother shared. Stepping into the washroom and closing the door behind her, Lisa hung her red towel and then started the shower in the warmest setting. Once she tested the water with her fingers and deemed it acceptable, Lisa stepped into the shower and closed the frosted glass door. As she washed her body, the steam from the warm water rose into the air, making strange patterns. It was as if the steam was being gently swept around by Lisa without the use of any body parts.

After several minutes, Lisa opened the shower door and stepped out. She thought she had heard the main door closing while she used her towel to wipe her body and then her hair. "Mark!!!" Lisa yelled out as she wrapped the towel around her body before tying off the top.

"Hey," Marked yelled out from just outside the washroom door, "are you done?"

Lisa opened the door after she was covered up for the most part; her shoulders were exposed, as was her still wet hair. Her eyes met her brother's, and a smile formed on her lips when he asked, "Had a good day?"

"Weird day," Lisa replied, walking past her brother before turning around to face him.

In that instant, when she had walked past him and turned around, Lisa did not catch him taking a sudden deep breath. Lisa smiled at him while wrapped in her towel and said, "I'll tell you what happened after I put some clothes on, after I take a nap thanks to this weird and exhausting day, and after you order something for us."

"You did something to yourself?" Mark asked while Lisa noticed his eyes lingering on her body before suddenly shifting up towards her eyes, "Something's different."

"Nothing's different," Lisa replied cheerfully before saying, "I'll see you after my nap."

"Yeah," Mark replied in a whisper, before Lisa turned and headed for her room. Stepping into her room, Lisa looked back over her shoulder at Mark, who had just turned around before stepping into the washroom. She didn't miss the look of longing on his face—- 'or was it just a trick of the warm washroom lights?' Shaking her head, Lisa closed the door behind her before unwrapping the towel and then drying her hair. She heard Mark leaving the washroom a few minutes later.

After drying her hair, she then sent a message to her best friend Sarah that she had just reached home and was about to take a nap. She then sent a message to Mark saying the exact same thing, except she added that she was going to be sleeping naked, so he needed to yell from outside her door if he needed anything.

"Too much information!" Mark yelled from his own room. Lisa laughed out loud before setting an alarm on her digital clock. Lying on the bed, she slipped under her cotton comforter, which gently brushed her dry and smooth skin. Once she was comfortable, Lisa slowly closed her eyes. As Lisa slept over the next couple of hours, her room filled with her pheromones. The invisible biochemicals eventually reached critical mass in her room since her windows were closed and the air conditioning kept her room cool. The biochemicals that continued exuding from her body began leaking under the door to her closet and filling it up. The pheromones were also leaking under the door to her room and into the hallway, where Mark was heading down the stairs to the living room with his phone against his ear, ordering pizza for dinner. After making the order, he would stride towards the couch and play some video games until the pizza was delivered.

Mark sat down on the couch after turning on the video game console and grabbing a controller. "I'll wake Lisa when the pizza's here." As the television and then the video game console turned on, Mark couldn't help but think back to the faint scent of Lisa's strawberry bodywash that rushed out of the washroom after Lisa opened the door. He had taken a deep breath after Lisa walked past, and almost immediately he felt his heart race watching his sister turn around to face him while the towel was wrapped around her body. He thought back to watching her shoulders, his eyes then travelling down from her shoulders to her towel-covered chest, and then down the rest of her body. Once he realised what he was doing, Mark thought back to shifting his eyes towards her face while trying to wonder what had just happened.

As the game entry screen came on, Mark pushed that thought away as just something that was in his imagination. Leaning forward on the couch, his controller at the ready, Mark unknowingly took in the first whiff of the biochemicals floating down the stairs from Lisa's room and into the living room.

Nearly thirty-five minutes after having called for the pizza, the doorbell rang. At the same time, Lisa stirred beneath her comforter just before her alarm rang. Her eyelids fluttered open, and she sighed at the time on the digital clock. 'Seven thirty,' she thought to herself as she slowly sat up on her bed while yawning. She shook her head while removing the comforter from her body. She then turned her body and shimmied towards the edge of the bed while the cool air in the room brushed against her skin. Lisa wiped her eyes with the back of her hands before turning on the light in her room.

'I smell strawberries,' Lisa thought to herself. But she put that thought away, thinking it was the scent of her strawberry-scented body wash lingering on her skin. Lisa heard the door downstairs close with a bang before hearing the sound of a car being driven away. Lisa stepped towards her door and then opened it slightly, unaware she was letting out even more of her pheromones into the house, and yelled, "Mark! I'm up!!!!"

"Cool!!!" Mark yelled back, "The pizza's here! Get down here!"

Lisa closed the door to her room, and almost immediately her supercharged pheromone production began the process of filling her room once again. Lisa was happy the tingling sensation was gone as she walked over to her closet and picked out a pair of knee-high black leggings and a plain blue and red T-shirt. She decided to forgo wearing any underwear since she was at home. Lisa then put on her leggings and then the shirt before reaching for the phone on her side table. She noticed an unread message from Sarah, so she sat on the edge of her bed and began typing out a reply.

It would be several minutes later that Lisa walked out of her room and then rushed down the stairs. Lisa smiled at Mark, who looked back at her while picking up a slice of pizza from the box on the coffee table in front of the couch. Lisa glanced at the pause screen of the racing game Mark was playing as she leaned down to grab a slice of pepperoni cheese with extra cheese. She did not notice Mark's eyes glancing at her shapely breasts before quickly looking away with confusion on his face.

She then, with her slice in hand, walked over towards one of the living room windows. All the while, as she was closing the curtains to cover the windows and asking Mark what movie he had in mind, Mark's eyes were on Lisa's ass. He focused on her ass cheeks, accentuated by the tight leggings she was wearing—the material hugging those globes—before looking away quickly when Lisa strode towards the other windows near the front door and in the dining room. She continued to pull all the curtains around the dining room and the kitchen closed. Lisa turned back towards the now darkened living room, with only some light leaching into the darkness from the top of the staircase.

Lisa was already holding only the crust of the pizza in her hand before she placed it in the box. "I'm eating that later." She then picked up another slice as Mark chuckled while Lisa sat down next to him. Mark handed her the remote control and told her she could watch whatever she wanted. His words surprised Lisa slightly; usually when they were home alone, Mark already had something in mind to watch. Shrugging her shoulders while shimmying closer and then leaning into her brother, Lisa turned to Netflix and began going through some of the shows their parents would not want her watching. 'Let's see how much I can push my luck,' Lisa thought just as Mark asked about school.