I stared right behind Derek for a moment: Runt was there, giving me an impish grin and nodding his head knowingly. In a moment, I felt my tiny cock getting rock hard again in my speedo, and my balls refilling with tainted roid cum.
"Wanna know what the hell's going on bro? Suck on this and you'll know it," I said the gym employee while pulling down my speedo to reveal my small erection. Derek looked at it with a derisive smirk for half a second, before his eyes glazed over and were filled with sudden lusty desire; the well-built man fell on his knees and put my tiny cock in his mouth, sucking on it like a pro. I let out a deep moan as I grabbed Derek's head and started face-fucking him while Thomas rubbed his massive body against mine, licking and kissing my thick veiny neck. As before, it only took me a couple of minutes to cum, spraying infected spunk down Derek's throat.
The gym employee let out a confused groan as his frame began to expand, his polo shirt ripping to shreds as the muscles of his back reached inhuman proportions. His biceps and triceps inflated so much he couldn't keep his arms straight, and even bending them properly was extremely difficult. His pecs developed into a meaty shelf of man meat topped by massive nips, and his flat stomach distended into a rotund and firm roid gut, the skin reddening and getting a bit blotched here and there. Derek's stubble disappeared, as did most of his hair, leaving him only with a black half-circle in the back of his head.
The man's tribal tattoo shimmered and radically changed shape, becoming the phrase "BORN 2 B JUICED" written in big blocky letters; even the black studs in his ears grew, becoming big fat shining diamond studs. Lastly, the shreds of his clothes coalesced into a new outfit: a skimpy sleeveless tank top with a tag reading "ROID MASTER" and a golden thong showing off his trunk-like legs and his meaty gigantic ass. Derek moaned in raw pleasure as he felt his dick shrink to baby proportions, before unloading his first roid boy orgasm inside his new thong.
"Wha... what happened?" he asked me, his eyes still hazy and unfocused. I pulled him closer and stuck my fat tongue in his mouth, and after a few seconds of confusion he reciprocated my kiss.
"You just became a sexy roid head, dude," I replied with a huge lusty grin. "Now come on, bros, we need to introduce all the other guys here at the gym to our way of life... Let's turn this place into a roid paradise."