The gentle throbbing below you was intense, and the more you felt your balls strain and grow the more you wanted to keep adding.
Grabbing three vials at once, you braced against the shelf and opened each cylinder to introduce the abandoned essence inside to it’s new home. Slowly but surely, they each in turn gravitated toward the tip of the cock before them, pushing inside slowly and traveling down before plopping into your ballsack with a cavernous sloshing sound. The last one moved slower than the rest, almost like it was struggling to move, but after some coaxing strokes it arrived outside your balls. You felt as the combined cum essence inside reached out to the newcomer before pulling it harshly toward itself until there was only one presence left.
You now had the cum production of six grown men within your body. You felt so full, so strained. It bubbled and broiled inside you, nowhere to go except to stay trapped in your testicles as they swelled far beyond their original human capacity with more flooding in by the second. If you let it out now there is no telling how much mess it could be - or when it would stop!