Chapter Text
Hermione Granger's sixth year at Hogwarts had been a whirlwind so far—intense classes, brewing tensions with the rise of Voldemort, and the constant weight of her role in the Order of the Phoenix. But as she boarded the Hogwarts Express on that crisp September afternoon in 1996, she felt a rare sense of relief. The scarlet steam engine chugged along the tracks from Platform 9¾, filled with the chatter of students reuniting after summer. Her trusty trunk, packed with books and a few illicit potions ingredients, was stowed away, and she had claimed a compartment with Harry, Ron, and Ginny. Except... something felt off this year.
As the train rattled out of London, a prefect from Ravenclaw—Penelope Clearwater, now in her seventh year—slid open the door to their compartment. She looked unusually flushed, her cheeks pink against her dark robes. "Hermione, Ginny—McGonagall wants all sixth- and seventh-year girls in the rear carriage. Immediately. It's... mandatory."
Hermione frowned, exchanging glances with Harry and Ron. "What for? Is it about the war? Security measures?"
Penelope shifted uncomfortably, her eyes darting away. "Not exactly. Just... come on. You'll see." She hurried off, calling to other girls down the corridor.
Ginny shrugged, grabbing her wand. "Weird, but okay. See you boys later?"
As they made their way to the rear, Hermione noticed clusters of older girls whispering nervously—Lavender Brown giggling with Parvati Patil, Cho Chang looking stoic beside Sue Li, and even Slytherins like Daphne Greengrass and Pansy Parkinson trailing along with haughty expressions. Fleur Delacour, visiting as Bill Weasley's fiancée, was there too, her Veela allure drawing stares, accompanied by her younger sister Gabrielle. The list went on: Alicia Spinnet, Angelina Johnson, Katie Bell from Gryffindor Quidditch; Hannah Abbott and Susan Bones from Hufflepuff; the Patil twins; Luna Lovegood with her dreamy gaze; Romilda Vane batting her eyelashes; and even the Carrow sisters, Flora and Hestia, looking sinister as ever. Nymphadora Tonks, disguised as a seventh-year for some undercover Order business, winked at Hermione. Astoria Greengrass and Tracey Davis rounded out the Slytherins, while Darcy Malfoy Heather Potter Rose Potter and Penelope herself made up the full count—28 girls in all.
They crammed into the rear carriage, which was unusually spacious, expanded by magic no doubt. Professor McGonagall stood at the front, her lips pursed, flanked by Madam Pomfrey. The air hummed with a faint enchantment, and Hermione's skin prickled—there was powerful magic at work here.
"Ladies," McGonagall began sternly, "as sixth- and seventh-years, you are now of age in the wizarding world. With that comes certain... traditions. The Hogwarts Express has long been more than a mere train; it's a rite of passage. To foster inter-house unity and... relieve tensions during these dark times, you will participate in the Enchanted Compartments."
Murmurs rippled through the group. Hermione's mind raced—what tradition? She'd read every Hogwarts history book and never heard of this.
McGonagall continued, her voice clipped. "You will each consume a Flexibility Potion—brewed by Professor Slughorn—to make your bodies more... adaptable. Additionally, a Lactation Charm will be applied for the duration of the journey. You will proceed to the upper level of this carriage, where compartments await. There, you will... position your enhanced assets—breasts and posteriors—through designated apertures in the floor. The students below, in the main carriages, will have access to... interact with them. Devices such as nipple clamps, dildos, vibrators, and other enchanted toys will be provided for their entertainment. Your milk will serve as refreshments."
The room erupted. "What?!" Hermione blurted, her face burning. "Professor, this is absurd! Indecent! We can't—"
"It's voluntary in name only," McGonagall interrupted, though her eyes betrayed discomfort. "Refusal means expulsion from the Express—and potentially Hogwarts. It's an ancient charm on the train, dating back to the founders. Salazar Slytherin himself enchanted it to 'build resilience' among the witches. In these times, Dumbledore insists it promotes... bonding."
Fleur crossed her arms, her accent thick with indignation. "Zis is outrageous! I am not some... dairy cow!"
Pansy sneered. "Speak for yourself, Delacour. Some of us might enjoy the attention."
Luna tilted her head. "Oh, I've read about this in The Quibbler. The Wrackspurts thrive on such energies. It could be quite enlightening."
Madam Pomfrey stepped forward, vials in hand. "The potion is safe—makes you flexible like rubber, no permanent harm. The charm wears off by Hogsmeade. Now, drink up."
One by one, they complied, some eagerly (Romilda smirked), others reluctantly. Hermione choked down the potion, feeling a warm stretchiness spread through her limbs. Her body felt pliable, like taffy. Then the charm hit—a tingle in her chest, and suddenly her breasts swelled slightly, heavy with milk. She gasped, clutching them. They were larger now, straining her robes.
"Up the ladder," McGonagall ordered, pointing to a hidden hatch. "Each to your assigned compartment. No wands allowed—leave them here."
The upper level was cramped, low-ceilinged, stuffy with no windows. Hermione crawled in, assigned to compartment 4/28. Cushions and blankets lined the floor, but the metal base was hot under her knees. Two holes awaited—one pair for her breasts, another for her ass. "This is madness," she muttered, stripping as instructed (robes only, panties optional). The flexibility helped; she positioned herself, pushing her enlarged breasts through the holes. They stretched unnaturally, popping through with a squelch. Her ass followed, the potion making it feasible despite the tightness.
Below, in the main carriages, students buzzed with excitement. Harry and Ron, oblivious at first, were pulled aside by Neville. "Mate, you won't believe this—it's the Breast Express tradition!"
Harry blinked. "The what?"
In the enchanted lower compartments, breasts and asses dangled from the ceiling like bizarre decorations. Each set was labeled by house and year, with trays of toys nearby: glowing nipple clamps that vibrated on command, self-lubricating dildos, feather-light vibrators enchanted to tease endlessly.
Hermione felt hands below—curious, groping. A clamp snapped onto her nipple, sending a shock. Milk leaked, and someone laughed, "Fresh Gryffindor milk! Tastes like pumpkin juice!"
She whimpered, flexible body twisting but stuck. This was just the beginning—the train had hours to go, and 27 other girls shared her fate.
Little did she know, her "customer" below was Draco Malfoy, smirking as he selected a vibrator. "Granger? This'll be fun