The remaining prisoners are dealt with quickly, already being fucked by the expanding bandit brotherhood en masse. As the last few finish bulking up and adding their smells to the mix, things remain jovial. The crowd generally moves down the hallway out of the prison complex, following the bandit king's plan on some mass-communicated instinct or other. Nate follows along in the trailing-behind wave of new converts, and everyone stays pretty handsy in the nude. The swarm passes through a few living facilities branching out of the caves, before reaching the surface lit by more than ventilation tunnels and the odd torch sconce.
The bandit king makes his way onto a large wooden stage in an open area outside the cave complex, standing behind a podium.
"These are the words that rule," he announces. "Form is Conquest. Know this, speak it with the certitude of magic, and with that spread our sexual strength. Assert our story, and with will made manifest flex both muscle and power. Your sweat of effort is power converting this world."
He flexes his arms and gazes up, meriting a few whoops from the bandit brotherhood and a good bit of mutual masturbating besides. But you learn something. He's not just being platitudinous or metaphorical, that was some form of spell instruction. An explanation about finer details of how the whole magical conversion literal fuckery smell works enters your mind. A few of the more sexual types get a bit bigger until they stand heads over the already-taller-than-average crowd. Some shrink down into dwarves, halflings, and doll-sized pranksters experimentally. There's a bit of changing size from moment to moment like some trick of perspective, even some suddenly multi-limbed folks. Animalistic shapes and anthropomorphized ideas manifest every so often, but it's still a niche fetish for now. Many cocks get even bigger, though a few condense down into those more proportional for normal men or forms more unusual yet, and you know in any case they'll figure out how to stretch someone to their limit then stretch that limit. Bodies have become something more malleable, and the smell of that manliness is beautiful.
"Go, my brothers, and expand our kingdom." the king says. "Claim the roads, conquer the villages, expand our fortress, do as you will before me. For the brotherhood!"
A few raised fists and cheers as the crowd disperses to do whatever. Men experiment with changing the local world through various unnecessarily sexy poses and just by masturbating. Stone walls are raised, trees are restructured, rations pop into existence from cumshots expanding into packages, a lot of people fuck each other just to fuck each other. The scent of manliness is all-suffusing, though spread across dozens of niches based on the influence of whatever specific brother called it out. A few buildings sprout up until the brotherhood caverns are a village to match any other, in just a few days of fucking straight.
The king reigns, deciding many debates of early design and fucking the brothers involved for the fun of it. At one point he expands his genitalia to be massive enough a whole group can service him at once, licking over his body and fondling his enlarged junk. A veritable river flow of cum mixing together results in filling up some massive pool of collective energy in a literal swimming pool. It's apparently going to be used to cast rituals, enough to change the whole region, though the brotherhood isn't sure to what ends just yet.