After staggering down the hall Ben has to stop as he feel the urge swelling and the lump pushing hard against his fingers as he grips at the back of his rear with one hand and leans on the wall with the other. The others look back at him.
"Ben...are you alright?"
"You have to keep moving!"
"I can't....My rear hurts too much!"
The others stare in horror as they watch Ben's pants tighten in the back tenting like their's did not too long ago. They see the strain on his face as he struggles to keep his body straight but slowly he's forced to push out his rear behind him as his pant steadily tighten in the back. Despite holding both hands against the wall and lean into it hard Ben can't stop the slow push he's feeling on his hips making them shift steadily back until his hands slip on the wall and Ben drop down onto his hands and knees and pushes his rear high up into the air behind him. HE feel the strain as he feel, inch by terrible inch, his tail push harder and harder into the inside of his pants and feel it twitching inside his underpants. He strains hard.
"Help me stand up.....please...."
The others are too scared by the spectacle unfolding in front of them to move as Ben feel his pants reach their limit and there is a tearing sound as his underpants start to push out the back of his pants then he feels them tighting against the slow push of his growing appendage. Then he feels a sense of relief as those tear too and a long ropey tail smooth and hairless pushes out and his pants relax to return to their usualy shape as then black fur quickly covers the tail as on the end grows a course brown tassel.