Published: May 14, 2024

My one-hundred and eighteenth caption, featuring a muscular Senpai with a lot of muscles…

All image credits go to cromwellb. I claim no ownership over the image used. Please support the artist!

All image credits go to their respective artists. I have and never will claim ownership over any image I've used or modified for a caption, and I always encourage you to check out the artist and their wider body of work when possible.

“Come now, focus!” My Sensei shouted as I threw all my weight behind my kicks, doing my best to knock over a dummy. It honestly wasn’t going too well for me.

The truth was, I hadn’t been able to focus on my martial arts training at all since Sensei had transformed. My Sensei, formerly one of the largest, most powerful men in the country, had previously won dozens of awards fighting in various tournaments both domestically and abroad. When he had visited Tokyo while on holiday, he (along with several other people) were exposed to a chemical leak from a nearby medical research facility. These “chemicals” actually turned out to be part of an experimental “gene therapy” program they had been running, trying to reassign genders without the need for surgery. The legal fallout from the event had taken months to settle down, but eventually (after receiving a base payout in addition to monthly reparations) Sensei returned home, a completely different person.

Though all of us were shocked, I was perhaps the most… enamored. Sensei had been turned into a towering, beautiful woman, with piercing amber eyes and long, bluish hair, a “side effect” of the chemical exposure. Despite her reduced mass, she was still as tall as she was originally, and though no longer quite as strong as before, she was twice as fast. Moves she had perviously used as a man were nearly as fast as lightning, and trying to track her in a fight was nearly impossible. I figured this out after having been effortlessly thrown over her shoulder several times, my arm pulled into the air and one of her feet planted straight against my neck.

Though Sensei was quite beautiful, her attitude had remained almost exactly the same. She was stern, no-nonsense, and 100% serious. Despite the initial uptick in dojo membership, most of the other students had quit after some time due to Sensei’s harsh training regimine, something that had only increased since her transformation. Now, I was the only one left. Though I could have left at any time like the others, something about Sensei kept me coming back every other day during the week.

“You’re hopeless!” She shouted as I leaned against my knees, feeling the sweat fall off of me in sheets. “How are you supposed to fight with a stance like that?”

“I’m sorry, Sensei. I will try harder.” I panted, looking up to see her amber eyes locked with my own as she kept her hands firmly planted on her hips. Though she was clearly annoyed with me, I couldn’t help but enjoy the way she looked at me, even now in my fatigue. “Please… I just don’t understand how to move like you do.”

“What do you mean? It’s so simple!” She boasted, flexing her arms as she walked over to the dummy. “Its all about combining your punches with your kicks. If you focus too much on one, you become too predictable, leaving you open to attack. Watch me, and observe! This is for your own benefit, not my own!”

With her usual, swift motions, she delivered a furious series of jabs, hooks, and punches to the hapless dummy, using both her hands and feet. Watching her in motion was a treat in itself, especially when her breasts would bounce around in her karate-gi, only held in check by her black belt. I couldn’t keep myself from leering. Before I could recompose myself, I was shocked to witness one of said breasts pop out of her karate-gi as the belt came loose, revealing the glistening feature to my virgin eyes. She wasn’t even wearing a bra! I immediately averted my eyes, feeling how red my face had suddenly become. She had seen my reaction, and I braced myself.

“I-I-I’m so s-sorry, Sensei!” I tried to apologize, standing up and turning away from her. “I’ll… go home now. I don’t want to bother you with my presence any longer.”

“Stop. Turn back to me.” She immediately halted, putting a firm hand on my left shoulder. I obeyed her command. “Good. Now open your eyes, slowly.”

I did as she ordered once more, opening my eyes slowly to see her removing the top of her karate-gi, fully revealing both of her breasts and her toned abs. As she let the clothing fall to her sides, it also revealed how defined her arms were as well. She hadn’t lost any of her muscle tone, and I found myself gobsmacked once again.

“Your training isn’t going to improve if you keep drooling over my form. Now, take a good look. Your curiosity no longer needs to distract you.” She huffed, sweat glistening on her skin. Though annoyed on the surface, she had a noticeable blush. “If I share my body with you, will you endeavor to do better in your training?”

“S-Share?” I repeated in a moment of total shock as she leaned in towards me, forcing me against the wall. “Sensei, are you sure t-that’s appropriate?”

“Don’t be coy. We’re both adults, and I’ve seen the way you look at me here.” She eased, her expression softening as she put her free hand against my leg, near my crotch. “I have my own… needs and desires too, you know. Don’t think I haven’t noticed the… gear you’re packing down there. Question is, are you willing to use it?”

I could have sworn her eyes practically glowed as I stood in her shadow, feeling more like prey or a cut of prime steak than a man. Still, as I looked back down at her ample bosom, chiseled abs, and tight biceps, I couldn’t help but meekly nod my head, the mental image of my old, male Senpai completely disappearing as she turned around, giving me a good look at her equally muscled back. She pulled down her pants, revealing a perfect, heart-shaped ass. Her glutes were just as well-toned as the rest of her body. Once again, I found myself completely entranced by her. She was perfect in every single way, and I knew from that exact moment I wanted her.

“Well, it seems your body agrees with me.” She smirked as she felt the outline of my shaft through my pants, which had only grown harder. “Now, here’s the deal. If you can satisfy me, make me feel like a real woman, we can think about turning this into a more… permanent arrangement. If you fail, however…”

Without another word, I immediately used every ounce of my strength to sweep her into my arms, feeling the immense heft of her body. Her amber eyes went wide in shock, completely ignoring the comedic image of my smaller frame struggling to carry her out of the dojo, into the small room in the back. Dropping her onto a pile of tatami mats, I ripped myself out of my own karate-gi, wasting no time worshiping every inch of Sensei’s body. Though she managed to take the lead back from me several times, using her immense muscles to do so, she always ended up letting me take it back, always with a blank, goofy expression of ecstasy on her face.

Hours later, we had thoroughly soaked through several of the tatami mats, covered with a mixture of sweat and… other things. Sensei had finally ended up in a position similar to my own earlier in the day, panting and sweating as she tried to catch her breath. Though she later joked that she had actually been the winner, a month later it was clear both of us had won. With a child now on the way, our relationship quickly changed, both of us becoming equals through our love for one another.