Andreas's body getting upgraded

Just as Andreas took a hold of his clean t-shirt, he felt something weird in his butt. It felt as if he needed to fart, while air at the same time entered his butt. He just lifted his eyebrows and shook it off as tiredness in the butt muscles after the training. He then proceeded with putting on his pants, which were some skinny chinos that hug his legs perfectly, only this time, they didn't get past his ass. He pulls and pulls but it just doesn't work. He walked over to the mirror and placed himself sideways to get a better look of what was happening around his butt and was horrified when he saw his ass expanding like two giant balloons. His ass was almost bigger than Linus's at this point and didn't slow down. A minute went by until his ass finally stopped expanding, to his surprise the new briefs hadn't burst and they made his ass look even bigger.

"I don't mind the briefs but this ass is obscenely large, I can't walk like this!" Andreas said to himself in the mirror.

Andreas felt his new cheeks and discovered that they were very sensitive to the touch and felt like the best texture gel he could ever feel. He took off his pants, or what he'd gotten on that far, and sat down on the bench. He noticed that he sat much higher now and much more comfortably, it was like sitting on two enormous pillows.

Next he felt how he really had to pee. Andreas got caught a bit by surprise as he hadn't felt anything before now and quickly ran to the toilet. He couldn't quite fit through the narrow toilet door but that didn't matter, he could stand. He tugged down his briefs slightly so he could let his above-average penis free to let him pee. To his horror however, his dick just fell and fell and fell until it hit the floor and continued to pile itself onto itself like a snake collecting itself when resting. It had to be at least 50 centimeters by now and still expanding, it was as thick as a coca-cola bottle. Luckily he could hold his pee and then exited the stall.