TWO YEARS EARLIER
Kelli Milagro Michel stood in front of her body length mirror in her underwear, critiquing her figure. She was getting ready for a date later that day but didn't really feel up to it. Her reflection was actually quite nice if you were to ask any random, hormone-crazed teenage boy, but she didn't think so. She saw a pudgy stomach that could stand to lose a couple pounds. Stretch marks around her thighs that looked more like scars than tiger stripes. An average forgettable face, at least to her. Kelli had never been too comfortable with how she looked. And until a month before, she had been resigned to thoughts that she would forever be an average, unfortunate, lonely soul.
Her mother would tell her that she was a miracle baby, her Milagrito. But being a twin had always been more of a curse. She couldn't do anything without being compared to Kacey. She'd actually be surprised if anybody outside of her parents saw them as two separate individuals. Birthdays were a combined effort. Boyfriends were out of the question. Shopping...well, shopping had been easy, just getting the same thing twice, until high school.
Ah, high school, the crucible of the teenage sex drive. Most students arrive innocent and untouched but leave physically, and spiritually changed forever. For Kelli, this change manifested itself in many things. She got braces, she joined the school orchestra, she found she had a secret crush on her sister.
That last part was something Kelli had went back and forth on since they started high school. The twins were as close as twins could be, literally doing everything together, and Kelli would be stupid to not admit that she saw Kacey's body change in a dramatic way. While Kelli's bras came at a modest 32B, Kacey had blossomed into 34DD. Her shape became more like an hourglass thanks to more weight going to her butt as well. Kelli couldn't envy her own sister, she literally had the same genes as her; she just adored her.
Kelli knew her affections were wrong to the outside world but she couldn't change it, no matter how hard she tried. However, longing from afar can only satisfy the eyes. To satisfy her body, Kelli turned to masturbation. And lots of it. Since she started high school, she spent most nights rubbing herself into blissful sleep, with Kacey's sumptuous body as her muse. She'd probably call herself the most sex deprived sex addict but how could she let anyone know about her desires? The thought alone was too much so she was content with her lewd imagination.
Kelli expected her senior year of high school to go similar to the previous three years. This initially meant lots of daydreaming, doodling, and dildos. It turned into an experience that would change her life.
One October morning, Kelli found herself daydreaming during math class. It was Homecoming Week, Pajama Day to be exact, and everybody had come to school in their sleepwear. Kelli had chosen to wear a loose pink exercise shirt and sweatpants with slippers to reach maximum comfortability. She felt pretty good on that day, but was strangely horny all morning. It was probably just from seeing Kacey in her cute pajamas.
Her math teacher had assigned a quick worksheet for the class to do. Kelli looked to her friend, Maddie, next to her.
"Hey, you wanna knock this out so we can just chill out the rest of the class?" Kelli asked.
"Yea. It should be easy enough. By the way, you and your sister are so cute. The matching outfits is so you."
"Thanks. I mean, it's just lounge wear. I feel like a bum really."
"Well, you don't look like one. You and Kacey have all the boys staring."
"Oh, stop it, Maddie."
"No, I will not stop complimenting you, cutie."
The attention made Kelli blush hard. It was something she wasn't all too familiar with. She had gotten plenty of compliments before from desperate teenage boys whose main fantasy was a threesome with her and her sister but this time was different. It not only felt more genuine but it meant more to Kelli because Maddie was attractive. Maddie, who had to be near the top of Kelli's Hottest Girls list, was so bubbly and perky, in more ways than one. It nearly made Kelli's insides melt.
Kelli tried to focus on her worksheet but her mind kept racing with inappropriate thoughts. What was going on with her? Her thighs clinched together, trying to hold in her urges. She looked to Maddie, who was still working away at the worksheet, and an image of her with a monstrous penis popped in her head. While most people would object to that kind of thing, Kelli couldn't get enough of futanari. She loved the combination of hyper masculinity and femininity, even drawing a couple original characters in her spare time. She wasn't against other kinks either like monster girls or bondage, she just enjoyed being free sexually. Why was she even thinking about this?
"Hey, Maddie. What did you get for number 5? The one with the hot dog." Kelli asked, trying to return to the task at hand.
"Yea, that's a hard one. I couldn't figure out how to get the volume of the cylinder. Isn't it base times height?" Maddie returned, tapping her pencil on the desk.
"Nah, it's pi times the radius squared times height. I just can't figure out how that is supposed to fit in the bun." Kelli rubbed her temples.
"Yea, who even needs a hot dog that big?" Maddie giggled. "I'm just gonna put down whatever I get and hopefully that's close enough."
What was in the air today? Kelli seemed to find sexual imagery in everything she saw. She could see Maddie's nipples poking through her shirt. All the math problems were about volume and length. Now, she knew she was a perv but this was just ridiculous. She scribbled some numbers absent-mindedly on the worksheet.
'It was just an exercise,' she thought to herself, 'I'm supposed to get things wrong." She put her head down on her desk to clear her head but as soon as she closed her eyes, Kelli's thoughts went straight to Kacey. She didn't know exactly why but she couldn't help but feel that while she looked cozy in her pajama attire, Kacey was able to make cozy look sexy. Her skin was the perfect shade of brown with no blemishes to be seen. Her hair was curly and bouncy with a natural shine. Probably what Kelli loved most was that Kacey had the most perfect butt she could think of. It sat up just right, it was toned from regular jogging, and it had the best jiggle to it. Kelli felt like it made sense that she found Kacey attractive. They had always been pretty close and who else would be better for her than her own sister. Kacey just had a vice grip on Kelli's thoughts. And her vagina for that matter.
She could feel her cotton panties getting wetter from the thought of her sister's tight body. Her thighs rubbed together under her desk but she was conscious enough to stay quiet save for a soft whimper and not draw attention. It felt like her mind was sabotaging her, though. Persistent thoughts of her sister's body crashing against hers, tongues racing across skin, and moans of pleasure filled her mind.
She was enraptured with her vulgar thoughts until she felt her shirt become tight, like someone was pulling it from behind. She opened her eyes and looked around but no one was behind her. Thankfully, nobody was paying attention to her.
Looking down, Kelli saw that her boobs were straining against the t-shirt fabric, her nipples threatening to poke through. A sudden need to fondle and squeeze her own breasts came over her like a wave, making her ignore her surroundings even more. Her hand, as if possessed, drifted to her engorged boobs. One tweak of her left nipple made her breath hitch. Her vision darkened and her body seized in place. It felt like one of her stronger orgasms happening in just a couple seconds. Sweat started rolling down the back on her neck. Trying to catch her breath and composure, she laid her head on the desk again. "What is going on?" she thought. Her thighs tried to tighten together but something obstructed them.
