Chapter 5: New World History Teacher
The throne was carved from the heartwood of the great tree at Ryudo Temple’s peak, enchanted to a gloss so deep it seemed to swallow the lamplight. Caster lounged upon it, one leg draped over an armrest, her chin propped on a fist. The ritual chamber hummed around her, a low thrum of latent power bleeding from the stone. Her mind chewed on the problem of the war.
Archer and Lancer were gone. Rider was still unknown. Shirou and the Tohsaka girl were essentially out of the war. Assassin died to Berserker. Gods Berserker. A phantom twinge of ancient fear, cold and sour, tightened her gut. She knew more than anyone how daunting a task it would be to kill Heracles. She needed more. She needed another piece on the board, tilted in her favor.
A soft, wet sound, rhythmically persistent, broke her concentration. She looked down.
Saber knelt on the stone dais between her thighs, her golden head bowed in fervent dedication. Her lips were stretched around Caster’s cock, working the length with a desperate, focused intensity that was almost religious. A strand of saliva connected her mouth to the base, glistening in the chamber’s ethereal glow. Her eyes were closed, her brow furrowed not in distress, but in deep concentration.
Caster watched her for a long moment, letting the sensation wash over her. The hot, tight pull of Saber’s mouth was a pleasant distraction, a living testament to her victory. She threaded her fingers through the knight’s silken hair, not guiding, just possessing.
“Your mouth has gotten better,” Caster mused, her voice echoing softly in the vaulted space. “Less righteous indignation, more applied technique.”
Saber didn’t stop. Her throat worked as she took Caster deeper, a choked, guttural sound vibrating around the shaft. Her hands, resting on her own bare thighs, clenched into fists.
Caster smiled. The memory of the bedroom, of the sword on the floor, of the hot seed she’d planted, was a constant warmth in her chest. This was no longer just corruption. It was cultivation.
“We need to talk strategy, my pet,” Caster said, her tone conversational. “And before you worry, you’re doing wonderfully. Don’t stop.”
Saber’s eyes flicked open, meeting Caster’s gaze for a fleeting second before focusing again on her task. The submission in them was complete, but a new, feverish intensity burned beneath.
“Berserker is impossible,” Caster continued, sighing as she pushed her hips forward, feeling the head of her cock bump the back of Saber’s throat. Saber gagged, tears springing to her eyes, but she pressed forward, swallowing convulsively. “Even you and I together would be splattered across this mountain. We need to even the scales.”
She pulled Saber’s head back by the hair, just enough to dislodge her with a soft, obscene pop. Saber gasped, her lips slick and swollen, a line of spit trailing from her chin.
“The boy and Rin are spent. No servants. But you told me something interesting,” Caster said, her thumb tracing the curve of Saber’s cheek. “While you were… less cooperative. You mentioned the Matou girl. Sakura.”
Saber blinked, her mind seeming to surface from a deep, carnal fog. “Sakura…?” Her voice was hoarse, ruined.
“You said she was close to Shirou. That she visited him often. That there was a… sickness about her.” Caster’s eyes glinted. “A Master reeks of their power, even when hiding. And a sick one leaks. You sensed it, didn’t you? In your knightly, protective way.”
Saber nodded slowly, the memory sharpening through the haze. The girl with the violet hair and the sad, soft eyes. The faint, cloying scent of decay that clung to her, masked by soap and politeness. She’d thought it a human illness. But now, filtered through Caster’s perception, it took on a different shape. “Crest Worms. The Matou lineage. It’s… possible.”
“Possible?” Caster laughed, a bright, chilling sound. “It’s likely. A girl like that, infested with those things… Zouken would have bound a Servant to her to keep her stable, to use her as a battery. It’s what I’d do.” Her expression turned speculative. “And if she has a Servant, she’s vulnerable. Isolated. Protected by a grandfather who sees her as cattle, and a brother who is… now dead." Killed by Rin and Shirou earlier in the war.
She guided Saber’s head back down, and Saber went eagerly, taking her deep again with a single, practiced motion. Caster leaned back on her throne, the plan crystallizing.
“Rider,” she said aloud, the class feeling right in her mouth. “That must be her servant.” Her fingers tightened in Saber’s hair, setting a harder, faster pace. Saber’s nose pressed into the smooth skin at the base, her throat working frantically to accommodate the intrusion. “We need her. Against Berserker. Whomever she is, broken to my will, just like you."
Saber moaned, the sound muffled and deep. Her body was rocking on her knees, her own need becoming a palpable throb between her legs. The talk of strategy, of targeting the gentle Sakura, should have sparked some ember of rebellion. Instead, it fed the dark, possessive fire inside her. They were building something. An empire of two, soon to be three.
“You’ll like that, won’t you?” Caster whispered, her breath catching as she felt her climax coiling. “Having a sister in servitude. Two even. Someone to share the burden of your… devotion.” She pumped into Saber’s mouth, fucking her face with short, sharp thrusts. “You can show her how to please me. How to take her master’s cock like a good little whore.”
The filthy words, the claiming tone, shattered the last of Saber’s coherence. Her own hand snaked between her legs, fingers plunging into her soaked cunt with desperate, frantic strokes. The chamber filled with the wet, lewd sounds of her fucking her own mouth and her own pussy in unison.
Caster watched, a queen observing her subject’s worship. “That’s it. Get yourself ready. Because when I come down your throat, I’m going to bend you over this throne and fuck that royal cunt of yours until you scream for mercy. ”
The image, vicious and explicit, triggered Saber’s orgasm. Her body locked, a silent scream contorting her features as her cunt clenched around her own fingers, gushing wetness that dripped onto the cold stone. The convulsions of her throat around Caster’s cock were the final undoing.
With a raw, grating shout, Caster shoved herself to the hilt and held there. Her release pulsed down Saber’s throat in thick, hot jets. Saber drank it, swallowing obediently through her own climax, tears streaming down her face from the effort and the overwhelming, degrading ecstasy of it.
When it was over, Caster slid from the throne, her cock slipping from Saber’s lips. Saber slumped forward, catching herself on her hands, coughing, her body trembling with aftershocks.
Caster stood over her, pulling her robe closed. She looked down at the disheveled knight, at the mix of spit and come glistening on her chin and breasts
Saber pushed herself to her knees, then to her feet. Her legs shook, but she held herself upright. The hollow emptiness was gone, filled now with a dark, purposeul warmth. She looked at her reflection in the polished black stone of the dais—a face flushed with use, lips bruised, eyes gleaming with a defeated gaze.
"Hmmm the school, the perfect place to corrupt the Matou girl to our side. And keep an eye out for your former allies."
The idea unfurled in Caster’s mind, perfectly formed. “Schools love foreign experts,” she said, her fingers still toying with Saber’s damp hair. “A visiting lecturer from Greece, specializing in pre-Classical myth and its… practical applications. It grants me access, a legitimate reason to be near them all.” She smiled, a cold, sharp thing. “And teachers see everything. Vulnerabilities. Alliances. Fear.”
Saber listened, kneeling in the aftermath, her own wetness cooling on her thighs. The plan was sound. Cunning. It tasted of Medea’s particular genius, a poison wrapped in plausible courtesy.
“You can’t come with me,” Caster stated, her voice leaving no room for debate. “A spectral form would be ideal, but that’s one trick your lovely shell can’t manage.” She traced the line of Saber’s jaw. “You’ll shadow me. Watch the perimeter. Your senses are sharp enough to detect another Servant’s presence if they get close.”
She leaned down, her lips brushing Saber’s ear. “And if you see your precious Shirou or that Tohsaka girl… you will not interfere. You will observe. You will report. You are mine.” To seal the command, her hand slipped between Saber’s legs, pushing two fingers back inside her with a cruel, sudden thrust. Saber jolted, a shocked gasp escaping her.
“Do you understand?” Caster whispered, her fingers curling, finding a tender spot deep inside that made Saber’s vision blur.
“Yes,” Saber choked out, her hips rocking involuntarily against the intrusion. “I understand.”
“Good.” Caster withdrew her fingers, slick and glistening, and brought them to Saber’s mouth. “Then clean your master’s hand. We have work to do.”
One week later, the air in Classroom 2-C smelled of chalk dust and adolescent apathy. Caster—now Medea Aetopoulos, according to the impeccably forged documents—stood before the blackboard, her posture elegant in a tailored charcoal suit. She wrote a single word in flowing Greek: Περσεφόνη.
“Persephone,” she said, her voice carrying a melodic, practiced warmth. “A story not of spring, but of a transaction. A king of the underworld desired a queen. He did not woo her. He took her. He opened the earth and swallowed her whole.” She turned, her gaze sweeping the rows of uniformed students. Her eyes lingered on a girl with long, violet hair sitting near the window. Sakura Matou’s head was bowed, but her posture was wire-tight. A faint, sickly-sweet aura, like rotting fruit and magic-choked soil, clung to her.
“Her mother raged,” Medea continued, walking slowly down the aisle. “She withheld life from the world. A famine of feeling. A bargain was struck.” She stopped beside Sakura’s desk, placing a slender hand on the cold laminate. Sakura flinched, almost imperceptibly. “The girl would spend part of the year in the light, part in the dark. A compromise between captivity and freedom.” She smiled, not at Sakura, but at the concept. “Was she a victim? Or did the darkness become her true kingdom?”
The bell rang. Students shuffled out. Sakure gathered her books with a quiet, hurried efficiency, avoiding the new teacher’s eyes. Medea watched her go, the cloying scent of Crest Worms receding like a bad memory.
Her next class was different. The air crackled with a tension that had nothing to do with mythology. She entered the room and saw them instantly: Shirou Emiya, with his stubbornly earnest face, and beside him, Rin Tohsaka, her beauty sharpened by a vigilant intelligence. Their eyes locked onto her with the force of a physical blow. Recognition, suspicion, and dawning horror warred in Rin’s expression. Shirou’s was simpler, a gut-deep alarm for a friend lost.
Medea’s smile never wavered. “Good afternoon,” she said, her voice a balm. “I am Medea Aetopoulos, your new world history instructor. Today, we discuss the fall of divine kingship.” She picked up a piece of chalk. “It often begins with a betrayal from within.”
From the rooftop of a nearby music store, Saber watched. The wind tugged at her hair, now tied back, her body concealed beneath a mundane coat. Her enhanced sight brought every detail into painful clarity: the windows of the school, the specific classroom where Caster—Medea—now stood teaching. Her gaze tracked the exits, the flow of students.
She saw Sakura emerge, a solitary, sad figure walking quickly toward the gates. She saw Rin and Shirou burst out a different door, their heads close in furious conversation. Her chest ached, a hollow pang that had nothing to do with mana. She remembered Rin’s strategizing, Shirou’s clumsy kindness. They were planning, right now, how to save her.
They didn’t know she didn’t want to be saved.
A flicker of movement in the shadow of a gingko tree near the school gate arrested her. A tall, impossibly slender woman with a waterfall of lavender hair stood perfectly still, her face obscured by the dappled shade. She was watching Sakura depart. The aura she gave off was muted, tightly controlled, but it sang of otherworldly power. A Servant.
Saber’s breath caught. Rider.
She focused, pushing her perception. The woman’s head turned, not toward Saber, but scanning the school’s entrance before immaterializimg, shifting back into her spirit form, presumably entering the school.
Saber’s focus snapped from the dispersing students to the empty spot under the gingko tree. A Servant, here, at the school. The air rippled where Rider had stood, a subtle distortion of light and magic that normal eyes wouldn’t perceive. It wasn’t an attack. It was reconnaissance.
A sharp, cold spike of adrenaline shot through her, the knight’s instinct roaring to life. She reached out through the new, burning connection of their contract, the mental channel that felt like a heated wire fused to her soul. ‘Caster. Be advised. You have company. A Servant, likely Rider, just entered the school. Do you require my assistance?’
The response came not as words, but as a sensation: a dismissive, curling wave of amusement, flavored with the faint, phantom taste of her own submission from that morning. It was a psychic pat on the head. ‘Stay your position. Observe.’
Inside the now-empty classroom, Medea erased the name “Persephone” from the blackboard with a slow, smooth stroke. The chalk dust hung in the slanted afternoon light like mist. She felt the presence solidify behind her the moment the door clicked shut, a pressure change in the room, a silence that was too complete.
She didn’t turn. “You know,” she said, her voice echoing lightly in the quiet room, “in my experience, Gorgons are rarely this subtle.
The air near the teacher’s desk shimmered, coalescing into the form of a woman so tall she had to slightly incline her head to avoid the ceiling light. Lavender hair fell in a sleek cascade. The black visor obscured her eyes, but the set of her mouth was a flat, guarded line. Her attire was sleek, modern, but it could not disguise the ancient, predatory stillness of her posture.
“And Princesses are rarely schoolteachers,” Rider replied, her voice low and measured, like stone sliding against stone.
Medea finally turned, leaning back against the blackboard. She surveyed Rider—the sharp angles, the hidden gaze, the proud defiance taut over a deep, weary resignation. It was a look she knew intimately from her own mirror centuries ago. A tool, discarded. A monster, made.
“We wear many masks,” Medea said, a faint smile touching her lips. “Some to deceive others. Some to remind ourselves who we once were. Which is this for you, I wonder?”
Rider didn’t flinch. “You are Caster. Medea of Colchis.” It wasn’t a question.
“And you are Rider. One of the Gorgons, though which one… Stheno? Euryale?” Medea’s eyes traveled over her with clinical appreciation. “No. The mortal one. Medusa.”
A muscle twitched in Rider’s jaw. The name, spoken so plainly, was a key turning in a long-locked door. “We know of each other, then. The witch who defied the gods for a love that turned to ash. And the maiden made monster for a god’s crime.”
“Used. Discarded. Our stories are hymns to pettier deities,” Medea said, pushing off from the blackboard. She took a step closer, the scent of her magic—incense and ozone—clashing with Rider’s aura of cold stone and deep saltwater. “Why break your meticulous observation? Your Master is already halfway home, trembling with every step.”
Rider’s hands, which had been held loosely at her sides, curled slightly. “My Master is dying.”
Three words. Hung in the chalk-dusted air. Medea’s smile didn’t fade, but it changed, sharpening into something more interested, more acquisitive. “The Crest Worms. Zouken’s filthy legacy. He was always a miser with his livestock. Feeds them just enough to keep them suffering.”
“Shinji Matou is dead,” Rider continued, the words blunt. “His role as a prana source is gone. The worms are starving. They will begin consuming her from the inside out soon. I lack the magecraft to stop it.”
Medea’s mind raced, connecting threads. The Matou girl’s aura of decay. The desperation in this proud Servant’s stoic delivery. She circled Rider slowly, a shark assessing wounded prey. “And you come to me. Not to kill me for my Holy Grail. But to ask for… help?” She let the word hang, ripe with mockery and possibility.
“I come to propose an alignment of interests,” Rider stated, turning her head to follow Medea’s path. “You seek the Grail. I seek to preserve my Master’s life. Berserker stands against us all.”
“Ah.” Medea stopped, facing her. “The great equalizer. Even the mighty Gorgon quails before the Mad Hero.” She tilted her head. “You believe I have a solution for your… resource problem.”
“You are a sorceress from the Age of Gods. Your knowledge of curses, of bounded fields, of parasitic familiars is unparalleled,” Rider said, her voice stripped of all plea, leaving only stark calculation. “If anyone can reconfigure the Matou system, or find an alternative sustenance, it is you.”
“And in return?” Medea’s gaze was a physical weight.
“In return, Rider-class services remain at your disposal for the duration of the war. Once my Master is stabilized.” The qualification was vital, a last thread of loyalty.
Medea laughed, a soft, knowing sound. “You want me to save your precious Sakura so you can both turn on me? My dear, I am many things, but I am not a philanthropist.” She stepped in close, invading Rider’s personal space. She could feel the coiled power in the taller woman, the lethal tension. “You want my help? You will be more than an ally. You will be mine. Your Master will be mine. A vassal state. My protection, in exchange for your absolute fealty.”
Rider was silent for a long moment. The hum of the fluorescent lights was the only sound. She was weighing the cost of a doomed, honorable defiance against the price of a vile salvation. “You would have to stabilize her first. I will not agree to her subjugation only for her to die in your care.”
“Naturally,” Medea purred. “But understand the terms. The ‘stabilization’ will be of my design. It will tie her to me as surely as those worms tie her to Zouken’s dirt.” She reached out, not to touch Rider, but to trace a finger along the edge of the teacher’s desk between them. “You reek of desperation, Medusa. It’s a familiar scent. I can work with it.”
Rider’s breath was a controlled, slow exhalation. “I will hear your proposed solution.”
“Not here.” Medea’s eyes flickered toward the window, toward the distant rooftop where she knew Saber watched. “Come to the temple at Ryūdōji tonight. Come alone. We will… discuss the practicalities.” Her smile returned, predatory and bright. “I assure you, I am very practical.”
Without another word, Rider’s form began to dissolve, fragmenting into particles of purple-grey light. “Tonight,” her voice echoed from the dissipating form, and then she was gone.
Medea stood alone in the classroom, the ghost of a triumphant smile on her lips. She could already see the pieces moving on her board: Saber, broken and loyal; Sakura, a dying battery ripe for repurposing; Rider, a formidable blade soon to have her hilt in Medea’s hand. Berserker’s seemingly invincible bulk suddenly looked less like a wall and more like an anvil against which she could hammer her enemies.
She gathered her things, the ordinary facade of the teacher settling back over her like a cloak. As she left the room, she sent another pulse through the bond to Saber, a cocktail of satisfaction, anticipation, and a sharp, unspoken command: Return to the temple. Now.
The main hall of Ryūdōji Temple was lit by a single, low brazier when Saber materialized at the foot of the wooden stairs. The coals cast a hellish, dancing glow over Caster, who was seated on her wooden throne, one leg crossed over the other. She was sipping from a cup of water, her expression one of deep contemplation.
“She came to you,” Saber stated, her voice flat. She didn’t approach the dais.
“She did.” Caster didn’t look at her, watching the flames. “Desperation makes the proudest knees bend. She wants me to save her little Master from the worms eating her alive.”
Saber processed this. The image of Sakura, gentle and sad, being consumed from within by those things stirred a faint, ghostly nausea. “Can you?”
“Can I?” Caster finally turned her head, the firelight carving shadows into her smirk. “I am Medea. The question is not ‘can I,’ but ‘how shall I.’ And the ‘how’ is what binds them to me forever.” She took a slow sip. “Rider will be here soon. You will watch. You will listen. You will see how a new sister is welcomed into our… household.”
The word ‘sister’ landed in Saber’s gut with a strange, cold weight. She saw again the phantom of Sakura, and now the stern, imposing Rider, kneeling where she had knelt. A shared corruption. The thought should have revolted her. Instead, a treacherous, hot flicker of something else—relief? anticipation?—stirred in the ashes of her will.
“You wish me to hide?” Saber asked, her tone carefully neutral.
Caster stood, descending the dais steps with a silent grace. “I wish you to serve.” She stopped before Saber, close enough for Saber to smell the incense on her skin and the sharp, clean scent of her power. “Rider’s loyalty is to her Master, not to me. Her submission will be transactional. Yours…” She reached out and took Saber’s chin in her cool fingers, tilting her face up. “…yours is cellular. I need to remind her of the difference. Of the cost of my generosity.”
Saber understood. A demonstration. Her role was to be the instrument of it.
“Take off your clothes,” Caster whispered, her thumb brushing Saber’s lower lip. “Kneel by the throne. Be my living ornament. My well-used pet.”
The command sparked no rebellion, only a hollow resignation that quickly flooded with a shameful, liquid heat. Saber’s hands went to the clasps of her battle gown. The fabric, a symbol of a sovereignty she had surrendered, pooled at her feet. The cool air of the temple raised goosebumps on her skin, but the heat from Caster’s gaze was more potent.
She walked to the side of the throne, the stone cold beneath her knees. She assumed the position Caster preferred: back straight, hands resting on her thighs, head bowed but eyes lifted slightly, watching. A statue of perfect surrender.
Caster resumed her seat, running a hand through Saber’s hair possessively. “Good girl,” she murmured, just as the space near the temple doors rippled and Rider materialized.
Rider took in the scene in one frozen instant: the sorceress on her makeshift throne, the firelight, and Saber—naked, collared by nothing but shame, kneeling like a devotional statue. Her expression, behind the visor, was unreadable, but her posture stiffened.
“Punctual,” Caster said, her voice smooth as oil. “I appreciate that. Come. Let us discuss your Master’s… dietary needs.”
Rider advanced, each step measured. Her gaze lingered on Saber for a fraction too long, a complex flicker of pity, recognition, and disdain passing over her features before she locked her attention on Caster. “You said you had a solution.”
“I do. The Matou system is crude. A leech that kills its host. It requires a external prana transfer, male in origin, to keep the worms satiated and the host alive. Correct?” Caster’s voice was clinical.
Rider gave a curt nod. “Shinji provided that. He is gone. The source is gone.”
“A source is merely a conduit,” Caster said, her free hand idly tracing the shell of Saber’s ear, making her shiver. “The power of a Servant is vast. My own reserves.” Her fingers trailed down Saber’s neck, over her clavicle, coming to rest on the top swell of her breast. “The issue is delivery. The worms are tuned to a specific, aggressive energy signature. Masculine. Forceful.”
“You’re speaking of a sexual transfer,” Rider stated, no inflection in her voice.
“The most efficient method, yes.” Caster’s hand cupped Saber’s breast, her thumb rubbing slow circles over the nipple, which hardened instantly under the touch. Saber kept her breathing even, her eyes fixed on a point on the floor near Rider’s feet.
Saber flushed, the memory of being filled, of being claimed, flashing through her with visceral intensity. Her cunt throbbed, a traitorous pulse of want.