None of this belongs to me... just this twisted relationship, but the rest is all JKs.
As Severus Snape enters his the dungeons, he finds his classroom full of Syltherins and Gryffindors. A hush fills the room as he sweeps to the front desk, staring, glaring down at their sixth year faces. He smiles when he spots Ginny Weasley in the back, flipping through the textbook. His eyes travel up her body, taking in her long soft pale legs, and he short skirt, up across her torso in her white button down with her black bra slightly showing through, the top three buttons of her shirt were undo. "Tsk, Tsk, Miss Weasley... You are not up to dress code. Please come to the front of the room."
She grumbles, stomping her feet a bit as she slowly makes her way to the front of the room, tugging down her skirt. The dungeon fills with a low whisper, the girls gossiping about how short Ginny's skirt was, and how you could see her bra! Ginny just smiles, and she sweeps her long flowing red hair over her shoulder, and turns towards the Professor.
Snape steps close, he towers over her height, giving him a look down her shirt, showing to nicely rounded tits enclosed in soft lace. Snape leans down, his lips resting against her ear. "Where did you get that bra Miss Weasley? I know your mother didn't buy it for you." Ginny glares up at him, the class leaning forward in their seats, trying to catch the whispered conversation. Snape turns, glares at them and orders "Turn to page 394 and make the anti venom poison for a snake bite, now!" the students snap to work, the sound of turning pages fills the room.
Snape looks down at Ginny, loving her eyes and how they light up with such wildness, his cock strains against his pants, she bites her lip, her little white teeth digging into the soft pinkness, she lick them, moisturizing them. "Get to work, Miss Weasley, I'll be expecting you at 8:00 for your detention. Do not be late."
Ginny looks up into his dark black eyes, and sees an emotion she knows well swirling in them... "Yes, Sir. Ill be here 8:00 sharp!" she flounces back to her desk, her short black skirt swishing back and forth. She sits down and crosses her legs, and sets to work on her potion.
Snape walks around the room inspecting all the students potions, belittling them, letting them know what a horrible job they were doing at this. Finally, he they finish their potions, and he orders them to do a page on what went wrong in each and everyone of their anti venom. The students grumble as they dash from the class... "Ah, Miss Weasley a word." Ginny hangs back, and walks up to Professor Snape's desk... "Yes, Sir?" she braces her hands on the desk, leaning forward, her full C breasts pushed together, the fourth button of her shirt having come undone.
Snape swallows... "Do not change, come into my office tonight and i will show you why you must wear the proper uniform." Ginny nods, throws her bag over her shoulder, as a quill falls out, she bends down, giving Snape a clear view of her ass. Ginny sticks it in the air, wiggling it a bit, and bends down for the quill, pretending to have trouble picking itup. Her skirt rides up so much that her black lace matching thong shows. Snape groans, and rubs his cock from the outside of his pants.
He walks up behind her, and grabs her hips, grinding his rock hard cock against her ass. He quickly casts a silencing charm, and he roughly brings down his hand, slapping her exposed ass cheeks. Ginny jerks, gasping, but Snape hold her hips hard with both hands. "Do not tease me, come back for your detention... now be gone" She flees from the room, blushing, her panties soaking wet just from the brief contact with her professor.
Ginny ducks into an empty hallway, her cunt begging for release, she slips her hand down her skirt, into her black lace thong, sliding against her bald pussy. She spreads the lips and smears her wetness against her clit, and rubs with two fingers against herself, moaning loudly, her hips jerking. One of her hands circles her throat, a thumb pressing in, choking herself as she finger fucks herself right in the middle of a hallway... she cums screaming out her release. She rights her clothes, buttoning her shirt all the way, and pulling down her skirt to the right length and goes to Transfiguration.