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Lysithea knocked on the door, clutching at the hem of her skirt. After a few moments that felt like a lifetime, she heard Byleth’s soft voice.
“Come in,” she said. Lysithea quickly wriggled her way through the door, shutting it promptly behind her. The professor’s quarters were plain, the only real signs of habitation were some papers from class and the professor herself.
“Lysithea,” Byleth started, a hint of confusion in her voice, “what can I help you with? I’m afraid I don’t have your paper graded just yet, if that’s what you’re here for.”
The petite mage’s face was hot with embarrassment. “Well, I… I had a bit of an accident. Magically speaking.”
A barely perceptible flash of concern spread across Byleth’s countenance. …8, 9, 10, she’s got all 10 fingers, she thought, and I still see eyebrows. “Is everything alright? Did anyone get hurt?”
“No - I mean, no one got hurt, but…”
Byleth couldn’t help but notice Lysithea’s penchant for covering her front, playing with her dress, and her embarrassed look. The former mercenary went straight to the point.
“Something wrong with your…?” She motioned her head down towards the girl’s crotch.
Lysithea’s face got even redder, but she nodded.
Byleth raised an eyebrow. “And you came to me instead of going to the infirmary because…?”
“I-Well, I was in the library and - well, before that, this one time with Professor Manuela, she - I mean…” She took a deep breath to compose herself. “A while ago, I had asked Professor Manuela if it was possible for magic to… maybe make me a little taller,” she admitted sheepishly.
Byleth looked up and down at the adorable girl in front of her. “I imagine she didn’t have the answer you were looking for.”
Lysithea was already too embarrassed and engrossed in her story to pick up on the jab. “No. In fact, she gave me quite the talking-to about abusing magic to alter my body.”
The professor’s thoughts briefly recalled Manuela drunkenly telling her how she used careful and consistent application of white magic to maintain a more youthful appearance. Probably best I keep that to myself. .
“So you didn’t heed her words, so you’d be too embarrassed to the infirmary for help.”
The mage fidgeted, seeming to adjust something between her legs, before nodding and continuing. “I was trying to reach a book the four- fifth shelf, and when I couldn’t reach it, some of the boys teased me, and I just… I couldn’t take it! Consequences be damned! I - I had already … found a spell in a book that was supposed to, quote, ‘add a few inches’, and it seemed simple enough.”
“And you just… trusted this book?”
“The book was practically falling apart, so many people had checked it out! The library card was filled with tons of guys’ names, and that specific page was practically in tatters! And so I got it ready and… I cast it a few hours ago…” She concluded, looking down at the ground.
Byleth scanned the girl one more time, certain she was no taller nor shorter than she was in class that afternoon. She hadn’t seemed to gain or lose any weight other, so Byleth was at a loss as to what this spell had done to her, and what it had to do with her genit-
Oh, sweet Seiros .
“Lysithea, have you sprouted a -”
Eyes scrunched shut and face scarlet as can be, Lysithea pulled her dress up and her tights down to reveal an adorable bulge in her white panties, bouncing in rhythm to her frantic heartbeat.
Byleth finally set down her pen, calmly took off her pair of red glasses, walked over and squatted in front of her befuddled student, and without fanfare, pulled her undergarment down. Springing to attention, all three inches of Lysithea’s erection pulsed in the cool air. Compelled more by curiosity than lust, the professor gently poked the pink head that peeked out of her foreskin.
Lysithea whimpered at the sudden stimulation, as minor as it was, with knocking knees.
How in the world did she manage to walk all the way over here in this state? Byleth thought. As she took her finger away, a surprisingly thick strand bridged it to her cock. Looking down she realized the inside of her student’s panties were smeared in pre-cum.
Byleth looked up. Lysithea looked to be on the verge of crying, desperately looking away as if that would make her problem disappear. The professor felt something she hadn’t been expecting: She very much wished to bully her adorable student. Resolute in her decision, she swooped the girl into her arms. Lysithea gasped quietly, her heart skipping a beat as she felt her professor’s muscles underneath her. Her bear-print panties dangled from her foot as Byleth placed her on the bed.
“Strip,” she commanded.
“P-Pardon!?”
Byleth flicked the tiny tadger between her pale thighs. Not enough to hurt, but hard enough she tensed and another pearl of slick welled up . “Take off your clothes. I obviously can’t take you into class, let alone battle, like this. I need to relieve your erection for now and I don’t want you getting your uniform any dirtier than it is. Now, strip.” There was barely any change in her words from normal, but on the inside, Byleth was quite delighted.
Lysithea, especially weak to following authority figures, complied. It also helped that she had fostered quite a crush on the beautiful and hardworking mercenary. She peeled off her boots and blue leggings, and with only the slightest hesitation, lifted her uniform up and off.
“Everything, Lysithea.”
Somehow more embarrassed by this, Lysithea undid the tiny bra that held back her perky A cups, setting it gently on the bed next to her folded uniform. Byleth’s eyes silently scoured her body, noting the stark contrasts compared to her own. Where Byleth was solid, toned, tanned, and scarred, Lysithea was petite, pale, and had hardly gained a pound in the five years she had been her student. Being far back away from most combat, her skin was smooth as porcelain and equally unblemished.
Byleth sat on the bed beside her, motioning her to lay across her lap. “I’m going to stroke you, and you just need to cum when I tell you to,” she explained matter-of-factly.
Before she could respond, the breath was knocked from her tiny chest by the pleasure of Byleth’s emotionless handjob. With a few strokes, her foreskin peeled back and exposed her incredibly sensitive head to the friction of Byleth’s palm. She began to struggle and squirm against the stimulation, but was easily held in place by the blue-haired swordmaster.
“P-Professor,” the restrained mage huffed, her breath high in her chest and eyes fluttering from pleasure, “please be gentle, I’m not used to - to…!”
“It’s only been a few seconds, Lysithea, just hold on and -” Byleth started, but before she could finish, she felt hot spurts of cum erupting in her hand. Surprised at her quickness, the sadistic professor opened her sticky hand, forcing Lysithea to ejaculate sans stimulation. Despite moments earlier whining about it, she now bucked and thrusted, desperate to salvage her first orgasm with her new cock. Held down by Byleth, there was nothing she could do as it pitifully throbbed and wept cum all over Lysithea’s thighs and scant white pubes.
After her orgasm ceased but before she could recover, Byleth returned to jerking Lysithea’s tiny cock with her now slippery, cum-stained hand. Its owner whimpered and thrashed more erratically than before, half laughing and half crying from overstimulation.
“P-P-Professor, please! I feel weird down there, l-like something big is coming!”
Byleth ignored her, even speeding up her pace. “I only gave you one instruction, Lysithea. You couldn’t even hold off for one minute. How are you going to be useful in a battle if you can’t even walk without staining your underwear?” The poor girl was too overstimulated to even form a response. Byleth noted with internal delight at the deeply red checks against Lysithea’s otherwise pale figure. “Now, as I was saying, you can come when I tell you to. We just need to build up your tolerance to -”
Lysithea let out another pathetic whimper as she once again began spurting out noticeably thinner ropes over Byleth’s fist. Byleth slid her thumb over her urethra, making the panting mage fight for every pump of her clenching balls.
Cute… , Byleth thought.
“Disgusting,” Byleth said, “Poor marks, Lysithea. No one likes a premature ejaculator, even if they’re a girl.” She took a tentative lick of her white hand. Her lip twitched; It was bitter and acrid. She wasn’t surprised by this, considering she knew the makeup of Lysithea’s diet.
Having come twice in almost as many minutes, Lysithea laid on the bed in a daze, her tummy covered in what jizz had escaped Byleth’s grip. She panted, exhausted in delirium from the tsunami of never before felt stimulation. Yet despite her back-to-back climaxes, her small cock still stood hard.
“I suppose this calls for a new plan. Instead, I am just going to make you keep coming until your freshly magicked testicles give up.” Byleth said, her hand reaching for Lysithea’s member.
“Professor, p-please, don’t touch it right away, it’s so sensitive,” she whimpered, her puppy dog eyes doing work on Byleth’s resolve. Not shaking it, but absolutely reaffirming it - This girl was too cute and Byleth wanted nothing more than to make her squirm in overwhelming pleasure.
“Very well.” Byleth stood up, letting her student have a singular moment of relief before flipping her legs up and over, her pale little bubble butt waving in the air. Byleth’s tongue quickly found her asshole, causing Lysithea to tense and gasp.
“P-Professor that’s dirty!” she moaned, already losing herself to the ashen demon’s ministrations.
“If I can’t touch it directly, I’ll have to stimulate it other ways.” Between the cum all over her and her own saliva, Byleth was easily able to slip in a slender, manicured finger. If this strange spell gave her a cock and balls, it stood to reason she’d have everything else, too, right?
She pressed her finger up, feeling validated as she heard Lysithea coo loudly. Byleth felt the soft hands of a scholar grip her muscular thighs as her victim tried in vain to right herself. She had found her pristine, untouched prostate, and wasted no time in bullying it.
Byleth adjusted her position, one hand on her petite chest, rubbing and pinching at her rosy pink nipples. The other was busy pressing away inside her ass, priming her cock for another mind-shattering orgasm. It didn’t take long for Lysithea to feel a new and more powerful sensation rising from within her. She had thought the sensation from Byleth’s handjob was incredible, and was now gasping and gripping the sheets and her professor as her toes curled and stars filled her eyes. After what seemed like barely three minutes, her girlcock was once again pumping load after load out on her belly. This time, she lost count of how many times it pulsed and hopped - it was by far the most intense orgasm she had ever felt, and in her mind, seemed to last forever.
“Come on,” Byleth said dryly, fondling away at her heaving breasts, “I think just five more of those and we can call it a night.”
After several tissues, a pair of used panties as a makeshift gag, a ruined bedsheet, and four orgasms later, Byleth released her sadistic grip on Lysithea. The poor warlock was covered in her own semen and sweat and had passed out multiple times, only to be dragged back to consciousness by careful application of white magic. Byleth had aimed to fry her brain and felt she had more than succeeded.
“Professor, please… no more. I… I don’t think I want to come anymore…”
“Are you giving up, Lysithea?” Byleth asked, silently impressed she had even lasted this long, “That’s a shame. I expected better of you. No matter. If you don’t want to come anymore, we’ll be done.” She reached into her pile of dirty laundry and flung a bath towel onto her. “Clean up. I’ll get the sheets. Your punishment for not completing your assignment is hardly even a punishment at all, considering you just told me you don’t want to come again. You will return to my office in two week's time, and I expect two things from you. First, you are not to ejaculate even once before then. Given your proclivity for… early release, I suggest you wear something less form-fitting down there. And don’t even think about masturbating. Second, see to it you start incorporating more fruits and vegetables into your diet. I’m not putting my mouth near your quickshot cock while your semen tastes closer to soured wine than cum.”
She wiped away the smeared mascara under Lysithea’s eyes. “Remember that this is the price you pay for experimenting with magic.”
“Y-Yes, ma’am,” Lysithea managed, her head still spinning.
“Good,” Byleth said, planting a delicate kiss on her student’s forehead. “Now go take a bath. You reek of squid and sweat.”