Every week I watched her. Just one hour a week! How my eyes feasted on her form. I was allowed to look: she was teacher. She stood at the front of the class, twisting herself into a series of crazy postures, which we all struggled vainly, flabbily, to copy. She was perfect. We trembled before her perfection – three old ladies, a skeletal teenager, and me. She didn't seem to notice us: it was as if we were viewing her own private ritual.

I stood at the back of the class and stared unashamedly. The whole hour, I gazed at her, willing my miserable self to copy her effortless grace. I took in every detail, drinking her in. The stark bones at her collar and wrists, the arch of her spine, the firm, pink nipples that grazed her t-shirt. She barely spoke as she moved: her few words sounded like a lullaby. “Deep breath...suck your belly in...drop your shoulders, relax your neck, your face, tilt your pelvis...” I did all she told me: willed my limbs to mirror hers. Week by week, they started to respond. I barely noticed. I only watched her. But she saw it, saw me, and started to smile at me now and then, when I skipped through the door, when my limbs lengthened, my spine flattened, according to her demand.

At the end of each class she turned the lights off for five minutes and instructed us to relax, breathe, meditate, feel the weight of the floor beneath us and sink into it. I spent that time thinking of all the things I'd like to do to her, given the chance. How I'd smooth my fingers over her elegant lean contours, before pushing her legs apart and delving into the hot wet essence of her, the filthy female essence I prayed lurked beneath her prim, controlled exterior. I would grab her buttocks and guide her on to my face, making her buck and moan as my teeth and tongue found her waiting and wet for me, tasting her, teasing her, nudging and sucking on her, forcing her to lose control, shriek and cavort like an animal caught in a trap.

Yesterday, I started to see how I might get my chance. She was distracted when her class trotted in, and when she began teaching, her movements were awkward almost clumsy. I stood at the back watching as she winced and limped through the motions, like a tiger stalking its wounded prey. All too soon, as ever, it was ever. But now was my chance! Surely I'd never find a better one. I'd not spoken to her before, only smiled. I screwed up all my courage and went up to her.

“You're having some trouble today?” My voice quivered a little at the start, but finished confident. In charge at last. She nodded at me, ruefully.

“I must have slept awkwardly. My shoulder's killing me. I can hardly move my right arm.” She demonstrated, wincing as she tried. I cleared my throat. “Would – would you like me to do a little work on that for you? I'm – I'm a trained masseur.”

She looked flustered, doubtful, then grateful. “Do you think it might help? I've got another two classes to teach today, and I don't know how I'll get through them.”

“I'll do my best”, I said firmly, trying and failing to keep the eagerness out of my voice. “Kneel down in front of me. That's it. Lower your neck.

Put your chin down on your chest. Just relax your limbs. Make yourself go floppy. And -” pushing my luck here, but what the hell - “close your eyes.”

She smiled, our usual positions so completely reversed, and did as she was told: sat in an obedient pile of pretty pink limbs at my feet. Flamboyantly I breathed on my hands and rubbed them, as if to warm them, though in truth I was sweating with excitement. Not attractive, not professional, but entirely unavoidable. She sighed, the tension leaving her, as I placed my hands on her shoulders, began to paw at her knotted flesh, still damp with sweat. Her breathing slowed. I watched her breasts rise and fall slowly under her t-shirt as relaxation swamped her. She trusted me. She was so used to forcing other bodies to submit to her will, there seemed nothing surprising about my instant command of her. Her skin was warm and soft to my touch. The muscles rippled, resisted, then parted for my fingers. I felt her loosen and yield to me. She sank still lower, presenting her neck to my mercy.

How far could I push her? I ran my fingers down over her spine, stroking out each nobbly bone. She didn't resist me: she barely seemed aware of me. I ran my hands over her hips; he sank obligingly lower, until she folded at the waist like a rag doll. “Perhaps”, I whispered to her, “You'd be better off lying down flat?”

“Mmm”. She let me rearrange her as I wished. I stroked her legs open, leggings still damp with sweat – or was it sweat? She murmured a little as I stroked up the back of her thighs. How taut they were, not a spare scrap of flesh! I kneaded them delicately with my fingertips. She sighed, and wriggled her legs further apart. I could smell her now, faint but distinct, animal and salty, rising from her crotch like an invitation. Without stopping to think, frightened to breathe in case I broke the spell,I moved my fingers between her legs, and continued my pretend massage there. My heart skipped a beat. Would she stop me, jump up, slap my face and storm off in disgust? Not in the least. She spread her legs wider, pushing her pelvic bone into the mat, lifting her buttock cheeks so I could easily reach her. I slid off her leggings, muttering some nonsense about how I could better manipulate her muscles unconstrained. No pants. I thought as much.

I would have stopped, I swear to God, if she'd given me a sign. Instead, her pussy lips rose to meet my fingers, engorged and red, juicy wet, throbbing, eager to meet my touch. I parted the damp curls and dived in. Her cunt clung to my fingers, forcing me inside. I found her clit and pulled at it gingerly, desperately, kissing my way down her back, watching her arch and contort in the mirror, her pretty dolly face screwed up with excitement, eyes still shut. Finally she came, a juddering, explosive climax that left my fingers dripping, squeezed at the constrictions of her clamouring, greedy cunt. She slumped down to the mat, all passion spent. I licked my fingers clean and left the room, allowing myself one final glance at her, hair a mess, legs still parted, a tiny puddle of pussy juice collecting between her thighs. Her eyes were still shut

I can't wait for the next class.