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🕑 Added 2025-08-01 09:13:40 +0000 UTCMike and Coach: Muscle Growth Diary
Mike (27 years old, 176cm, 85kg) was a man filled with a burning desire for muscle. Every morning, he eagerly headed to the gym, lifting barbells and pull-up bars to test his limits. His penis, typically 17cm, was a size he found satisfactory, but deep down, he yearned for a stronger, more massive physique. One day, as usual, Mike arrived at the gym and noticed an unfamiliar face—the newly arrived coach. The coach always wore tight pants, where the outline of what seemed like an extra leg, resembling a log, was strikingly visible. Mike couldn’t help but wonder inwardly, ‘Could that really be his penis…?’ blending surprise with curiosity.
Over the next few days, Mike found himself visiting the gym more diligently, less for the coach’s training methods and more to catch a glimpse of him. The coach’s muscles seemed like a sculpted masterpiece, and with each look, a strange attraction grew within Mike. One day after a workout, Mike followed the coach into the shower room. The coach was already under the water, his massive muscles glistening as droplets bounced off them. As he began washing his 95cm penis, it took considerable time due to its sheer size. As water cascaded over it, the 32cm-thick member glistened, with what appeared to be pre-cum faintly visible, and at one point, it seemed to harden slightly. Mike, catching sight of this, instinctively looked away, feeling an even stronger pull toward the coach’s muscles and overwhelming presence.
Noticing Mike approaching, the coach finished his shower and headed to the locker room to dry off. Unable to resist, Mike quietly followed. In the locker room, the coach, aware of Mike’s pursuit, turned sharply with clear intent. Suddenly, the coach’s enormous chest muscles loomed before Mike’s eyes, their firmness and protrusion shimmering with water droplets, dominating his view. But that wasn’t all—intentionally stepping closer, the coach’s 95cm penis slid between Mike’s thighs. The coach subtly moved his hips back and forth, creating a friction that made Mike’s breath catch. Internally, Mike thought, ‘I’m going crazy because of the coach’s penis…’ as confusion and excitement swirled within him. His body reacted naturally, his penis hardening visibly.
The coach, observing this, grinned slyly. “Oh, member, your body’s being honest. That’s quite an impressive potential, isn’t it?” he said with a wink. Mike’s face flushed red as he stammered, “Oh, I… I’m sorry!” trying to cover himself with his hands. The coach stepped closer, chuckling, “No need to apologize. This reaction makes it even more interesting,” his tone playful. Mike fumbled, “N-no… there’s no need for that…” and tried to step back, but the coach quipped, “I get it, you’re shy. Don’t worry, I was shy like you at first too. But look at me now.” He flexed his arm to show off his muscles and winked. Mike swallowed hard, muttering, “Th-that’s… really amazing…” The coach, gaining more confidence, approached further. “The amazing part is just beginning. Don’t you want to be like me? With muscles and confidence?” Mike hesitated, replying softly, “Um… I’d like to try…”
The coach smiled approvingly, placing a hand on Mike’s shoulder. “Great, then I’ll help you. But it’s not just about building muscle—I’ll share the secret to this body too. How about it?” Mike looked up, asking, “A secret?” The coach grinned mischievously, “Yeah, I broke through a plateau with this supplement. Want to try it? The effects are guaranteed. Side effect? Maybe a bit of extra stamina. No big deal.” Drawn by the coach’s commanding presence, Mike nodded without hesitation. The coach handed him several months’ worth of the supplement. “And,” he added with a sly smile, “if you grow to my level, I’ll give you a special reward. Look forward to it.”
Growth Diary
Week 1: A week after starting the supplement, Mike noticed his weight had increased by 10kg. His muscle mass visibly grew, making his clothes feel tight. Nights were filled with a strange excitement that kept him awake, though oddly, he felt no fatigue—only a sense of exhilaration.
Week 2: His muscles grew firmer, with his thighs and chest swelling noticeably. His penis seemed slightly larger, and his stamina surged. Mike enjoyed admiring his progress in the mirror every day.
Month 1: After a month, Mike was unrecognizable. His body had ballooned to a muscular 150kg, and he struggled to find fitting shorts. His penis grew more prominent, its outline becoming more defined, with pre-cum seeping out even when soft. Once erect, it wouldn’t subside, forcing Mike to masturbate discreetly in restrooms or parks a few times. The intense pleasure mixed with the thrill of his expanding physique.
Month 2: His muscle mass neared 200kg, and his penis surpassed 50cm. His stamina exploded, allowing him to masturbate consecutively five times with ease, and some days he managed 20 sessions. Yet his energy never waned, and his semen volume increased to around 500ml per ejaculation. Mike became consumed by this endless desire, craving further transformation. His conversations with the coach deepened, and he began to sense a special bond forming.
Month 3: Mike’s growth peaked. Now a 250kg muscle monster, his penis stabilized at 85cm, slightly shorter than the coach’s. His relationship with the coach transcended the typical coach-member dynamic, and their shower room encounters grew more intense. One night, overwhelmed by desire, Mike secluded himself in his room. He gripped his 85cm penis with his massive hands, its weight and heat almost burning his palms. As he began stroking, it hardened instantly. Pre-cum flowed endlessly, soaking his hands as he gripped harder. “Hah… hah… my penis won’t even fit in two hands anymore…” he panted. His breathing grew ragged, his body trembling as he moaned, “Ahh… I’m gonna cum again…” The first ejaculation unleashed nearly 2L of semen across the floor. But his desire persisted. Gazing at his reflection, he fell into a trance. “These muscles… this body… so perfect…” he murmured, lost in self-pleasure. He grabbed himself again, thrusting harder and twisting his hips. His tensed muscles amplified the ecstasy, leading to second and third ejaculations. The room became drenched in semen, yet his stamina remained. Exerting his last strength, he stroked once more, collapsing with a final groan amid the overwhelming climax.
A few days later, Mike and the coach’s relationship evolved into a deeper trust. One night, the coach invited Mike to a private training room. “Member, you’re almost at my level now. How about a special training session?” he said with a sly smile. Mike nodded, a mix of nervousness and excitement in his chest. The room was dimly lit, and their massive bodies faced each other. The coach began inspecting Mike’s muscles, running his hands over the hard, chiseled pecs, tracing the raised ridges and taut skin. His thighs were like steel pillars, thick and unyielding, while his arms bulged as if ready to burst. Mike’s 85cm penis hung heavily, radiating heat, its size and girth causing the coach’s gaze to flicker briefly. “These muscles… this penis… incredible progress,” the coach muttered in a low voice.In that moment, the coach’s breathing grew heavy with rising excitement. Unable to hold back, he laid Mike on the floor and spread his legs. “Too impressive… I want to feel you more now,” he said, pushing his 95cm penis into Mike’s anus. The initial pressure drew a moan from Mike as he gasped, “Ahh… Coach… it’s too big…” The coach, driven deeper by the words, thrust further, saying, “Yeah, show me what I’ve created.” Overwhelmed by the coach’s physique and strength, Mike pleaded, “Coach… please… put it in more… harder…” his voice desperate.The coach picked up the pace, responding, “Good, I’ll give you what you want. Feel my penis properly,” moving rhythmically. Mike trembled with pleasure, panting, “Ahh… Coach… it feels so good… my body belongs to you…” The coach replied, “That’s right, you’re my creation. I perfected this body,” savoring Mike’s reaction. As climax approached, Mike cried out, “Coach… I’m gonna cum…!” and the coach said, “Hold on a bit. I’ll go first.” Mike gritted his teeth, enduring until the coach said, “Now, let’s do it together,” and they reached orgasm simultaneously. The coach’s semen filled Mike, while Mike released nearly 2L of semen, collapsing in exhaustion. The coach embraced him, smiling, “Well done, my impressive student. Let’s go harder next time.”Mike’s journey was far from over. The coach’s next proposal awaited, and his body and mind would continue to grow endlessly.
Mike pre-growth: Height 176cm, Weight 85kg, Penis 17cm > Post-growth: Height 176cm, Weight 250kg, Penis 85cm
Coach: Height 189cm, Weight 270kg, Penis 95cm
Comments
Rekvar
Coach and student relationships are so good for muscle growth stories, I hope we see more of them in the future!
Brawnophile
Oh hell yeah! Mike really benefited from the Coach's secret supplement. Love how BIG he grew and that his reward (which was no surprise at all) was to get plowed hard by the Coach's massive penis. I can see these two pushing each other to grow even bigger in the future.
