Chemistry Girl Ch. 02

Mark continued to groan, his eyes closed, pleasure rushing through his body as his sister continued to stroke him while giving him a blowjob, which was so very taboo. It didn't matter, though. The fact that he had eaten his sister's pussycat didn't matter, so the fact that his sister was sucking his cock didn't matter either. He looked down to see her saliva coating his shaft, her right hand using it as lubrication while stroking it. He groaned while watching her take nearly half of his length into her mouth before pulling back and then going down his length once again. He tried to think straight: 'fuck, Kendra would be shit! She would be gagging by now. Oh, God!! So... fuck!!!' Mark was staring at the top of Lisa's head as he gently placed his hands on the sides of her head once again. She stopped stroking his shaft, and her lips were around his glans when she shifted her eyes upwards. Their eyes met.

All that Mark felt was intense pleasure and the desire to release the cum that had been collecting in his balls. The remains of cum that still remained on Lisa's sweat-covered face didn't help matters. But he forced himself not to cum yet. No, not yet, anyway. "If you want me to stop... fuck..." Mark closed his eyes in pleasure since Lisa continued caressing his cock glans with her tongue. He gulped and then opened his eyes again to say, "Slap my ass." Lisa nodded her head and hummed, creating even more waves of pleasure to go through him. Holding her head with both hands, Mark slowly pushed in more of his cock as Lisa's eyes widened while she placed the hand that had been stroking him on his left ass cheek. Mark felt her hands squeeze his ass, so he continued until he felt the back of her throat, and he still had about an inch and a half left to go. He could hear Lisa gurgle while her hands continued to squeeze his ass.

"Breathe in... fuck!" Breathe through your nose!!" He cried out while feeling her mouth fill with saliva, which, in turn, was surrounding his cock. He pulled his cock out of her mouth and watched as saliva dripped from around his cock and from her mouth. She looked up at him; her face was flushed, and her chest heaved. Mark saw that her nipples were hard and at attention. His eyes then focused on her lips before he told her to open her mouth and then guided his cock into her warm mouth once again. This time, he began to slowly fuck her mouth. He watched through a haze as he held her head while moving his hips like a piston, shoving his cock into Lisa's ready and willing mouth. He couldn't have imagined this. No way could he have imagined this very scenario ever happening.

After just a few minutes, Mark couldn't hold back any longer. Lisa's mouth was just too sensual. As he pumped his cock in and out, he tightened his grip on Lisa's head and thrust his cock as far as possible into the back of her throat. Lisa smacked his ass with both hands as cum filled her mouth, and he withdrew slowly. His cock was covered in a mixture of his own cum and Lisa's saliva, both of which were dripping out of her mouth. Mark saw her looking up at him with tears coming out of her eyes as she closed her mouth and gulped.

"Fuck, that's just so hot," Mark whispered between deep breaths as he helped Lisa slowly stand up, their eyes locked on each other.

Lisa nodded her head, a smile on her face, and the taste of her brother's cum still on her tongue, lips, and the back of her throat. She wiped her chin with the back of her right hand as she recalled how full her mouth had been; it was as if she had drunk a full glass of thick, slightly salty milk mixed with her own saliva. "That... that was... wow," Lisa said. Mark chuckled before saying he wasn't done. Lisa felt his hands on her arms before he told her to turn around. Guessing what was about to happen next, Lisa bit the bottom of her lip before saying, "What happened to going up to Mom and Dad's room?"

"Later," he replied before turning her around. Lisa heard him say, "Bend." And so Lisa did so by placing both her knees, one after another, on the couch cushions, her hands pressed against the covered wooden board that made up the rear structure of the couch. She looked over her shoulder at the lust etched on her brother's face as he grabbed his cock and slightly bent his knees. Closing her eyes and taking a deep breath, Lisa could feel Mark grabbing either side of her hips with his hands and then slowly pushing his stiff cock through the tear in her leggings, then through the outer lips of her pussy, and finally through the inner lips until he was inside her.

"Fuuuuuuck!" she cried out as she bent over even more, her head now lying on its side pressed against the back of the couch. In the most pleasurable way possible, she felt as if Mark's cock was tearing her in half. "Mark... fuck me... Fuck me." Lisa begged. She didn't really have to since Mark pulled out and slammed his cock back into her pussy, resulting in Lisa burying her face into the back of the couch and screaming out in pleasure. He was fucking her harder and faster, and Lisa's screams were muffled by the cushion. Although Mark could hear her exclaim, "Harder! Harder!!! Fuck your sister harder!!" Lisa raised her head and screamed in pleasure, "Aaaaaah! Faster!!! Fuck!!! Don't stop fucking me! Don't ever stop!!" Lisa's screaming continued, spittle flying out of her open mouth as Mark grunted while slamming his cock into his sister's dripping wet cunt. Lisa could feel explosions of pleasure throughout her body, even more than when he was licking her pussy several minutes ago.

A quick thought passed through Lisa's mind about the curtains in the living room and dining room: they were already pulled closed so that she and Mark could watch movies. She was thankful, or else anyone else could see them fucking from outside. That thought was immediately pushed aside as she screamed again; this time her body tensed as her eyes closed tight. She could see what seemed like brightly coloured explosions behind her eyelids as waves of intense pleasure crashed throughout her body, from her feet to the top of her head. Lisa could still feel Mark fucking her as if his cock was a piston. Oh, it felt so good.

"I'm going to... cum!" Mark exclaimed as he sped up. He could feel a tightness around his balls once again. Oh, his sister's pussy was so fucking tight and warm. He felt its walls pulsing and trying to squeeze his cock while Lisa's body tensed. He knew Lisa was going through an orgasm, and it made him excited. He was so excited; he could feel his cock about to shoot inside her. And, oh, how he wanted to shoot his cum inside her.

And Lisa wanted him to cum inside her. She wanted to know what it felt like to have his warm cum inside her. Lisa knew she wasn't on birth control yet, but she intended to go to the pharmacy after school the next day. She wasn't going to stop fucking her brother, that was for sure. No matter how taboo it was, she wasn't going to stop.

Opening her eyes, she looked over her shoulder at her brother, whose body was covered in sweat, and exclaimed, "Cum inside me... Fuck me, Mark! Cum inside me!"

Mark exclaimed, "Fuck yes!" just before thrusting his cock deeply into her cunt. He grunted before yelling, "I'm cumming... Fuck, I'm cumming!"

Lisa exclaimed in delight, "Ahhhhhhh... fuck... fuck... I can feel it... so warm... So warm... fuck!" She felt Mark's cock throb inside her as it continued to shoot more of his seed into her body. And it really felt so good. Lisa's back was arched, her hands grabbing tight onto the back of the couch, her head forward with her eyes closed shut. Mark's cock remained in her cunt seconds after he had emptied into her; she could feel his cock remaining still inside her pussy. His cock was still hard. As she slowly started to get down from her orgasm, her body eased up. She looked back over her left shoulder and could just see Mark staring down at her ass. "That was so good." Lisa suddenly felt Mark's hands tighten on her hips. She felt him slowly withdraw his cock before thrusting it back into her cunt. Lisa yelled out "fuck!" as Mark began fucking her once again. This time, he didn't start slow. Instead, he rammed his cock into her hard; she could feel his entire cock going into her, his balls slapping against her bare pussy lips.

Mark was grunting. He repeatedly pulled back his cock halfway and then thrust it back into Lisa's wet cunt. Looking back up at his sister's sweaty back, her screams muffled by the cushion, Mark sped up his to-and-fro motion. He had already cum heavily a few times, and he could feel as if his strength were being drained. However, her voice rang in his head, just as it had rang earlier when Lisa was in the throes of passion and telling him to continue eating her pussy. This time, her voice telling him; No, commanding him to fuck her hard and to not stop fucking her, rang in his ears. Mark didn't know if he could do it, but he would definitely try.

Lisa lifted her head from the couch cushion and exclaimed, "Fuck me... Fuck me, baby." And she screamed "AAAAHHHHHHH!" just before she quickly lowered her head onto the cushion once again. She released another scream, this time muffled as her body tensed about the same time as Mark, whose cock was rammed deep into Lisa before shooting more cum into her. Lisa could feel her own juices and his cum beginning to overflow out of her pussy.

She was panting hard while Mark's cock remained in her pussy. She looked over her shoulder once again, her face completely covered in sweat, with drops of the clear liquid falling down from all over her body and onto the tanned couch cushion below her. Lisa could see Mark looking exhausted; he was breathing hard while staring at her ass. Lisa whispered his name, and he looked up. Their eyes met. And his facial expression changed almost immediately.

There was a part of her that felt scared. His expression turned from one of exhaustion to one of pure lust. Before Lisa could say anything, his grip on her hips tightened once again before he pulled back his hips. Lisa felt his cock pull halfway out before being rammed into her again. Lisa screamed at the pleasure going through her once again. She was being pounded once again. She never thought anyone would be able to go on like this, but for now, she didn't care. Alternating between moans and screams was the most satisfying aspect of this fucking. "Baby, don't stop... Don't stop." This time, the length at which Mark fucked her was longer, but his cock was still hard and being driven deep within her cunt. Lisa begged him not to stop; to continue fucking her forever. She could feel even more explosions of pleasure go through her entire body as she experienced an orgasm.

"Fuuuuuuuck!!!!" A few minutes later, Lisa screamed into the cushion as her body tensed during another orgasm, just before she felt Mar's cock explode inside her. But this time, the throbbing of Mark's cock seemed to be weaker. Still breathing hard and slowly coming down from her latest high, Lisa looked back at the extreme exhaustion on Mark's face as he stared at her ass. There was something within her that could tell something was terribly wrong. She could see Mark panting hard; his whole body was covered in sweat, and parts of it were flushed. Their eyes met once again without Lisa saying anything this time, and that look of exhaustion turned to one of lust once again.

She felt his hands tighten on her hips, and he pulled his cock back. Lisa quickly yelled at Mark to stop. "You look exhausted," she continued. The look of lust on his face turned to one of exhaustion. She didn't have much time to linger on it as she closed her eyes and moaned when Mark slowly pulled his cock out of her pussy. She opened her eyes and watched Mark as he formed a gentle smile on his face while staring at her ass. He then looked up and said, "Damn, it's like a cum juice river flowing out of you." Lisa could feel it now—liquid travelling down the bare parts of her legs not covered by the leggings. She brought her knees off the couch cushions one after another as Mark stepped back. However, he stumbled back, only regaining his balance after nearly falling ass-first onto the coffee table.

"Mark!" Lisa called out as she rushed towards him before grabbing his right arm. Her heart was still racing, and she felt exhausted; even her pussy fell sore from all the pounding just now. She didn't want to know how much time had passed as she slowly helped her brother, who was leaning into her and slightly limping, to a dry section of the couch and helped him take a seat.

He leaned back while breathing hard. Lisa quickly rushed to the kitchen, her bare breasts bouncing, before she nearly slipped and fell onto the tiled floor since the soles of her feet were slick with sweat. She carefully walked to the fridge and took out a bottle of Gatorade, which was nearly three-quarters full. She took a few sips, her body tingling at the sensation of the cold liquid travelling down her throat. Then, she carefully strode out of the kitchen and handed her brother the bottle after taking off the cap. She watched as Mark drank the bottle until it was empty.

"Fuck," Mark whispered in relief as he handed the bottle back to his sister, who then placed it on the coffee table before sitting next to him. He put an arm around her shoulder as she leaned into him and placed her head just below his left shoulder. "That was... wow..."

"I know," Lisa replied. She was still coming down from her high, but her mind couldn't help but remember the look on Mark's face before asking him to stop. She knew he was exhausted but wondered if he would have continued fucking her if she hadn't said anything. There were so many other questions forming as her mind started to clear: What did this mean for them? Would they still continue to fuck? Was this just a one-time thing? Lisa really hoped it wouldn't be a one-time thing. Taking a deep breath, Lisa asked, "Would you have fucked me if I didn't tell you to stop?" Lisa was resting her head on Mark's sweat-covered shoulder, but she didn't receive an answer to her question. Worried, Lisa raised her head and looked up at Mark, and a tired smile formed on her face. Mark had his eyes closed and was fast asleep.

She returned her head to where it had been resting, turned her body towards her brother, brought her legs up onto the couch, and then placed an arm across his sweaty abdomen. Breathing out a sigh, Lisa then closed her eyes and gave in to her exhaustion.