Timmy didn't understand why Tommy went to the bathroom in the most exciting moment in the film. He can't wait for Tommy, he needed to keep watching. So, he spread himself on the couch and grabbed a bag of chips while the movie goes on. The curtains were closed and it was pretty dark in there, despite it wasn't very late yet.
Timmy was wearing just some baggy shorts, a gray t-shirt and his underwear. His clothes were so baggy that he didn't notice he was changing, he was growing. His thin legs were getting meat on their bones at an very fast rate that his feet got out of the couch in a matter of seconds. Those feet were also enlarging and going from a size 5 to an impressive size 14. They also got some meat and now they look thick and sturdy.
His torso was lengthening too, but it was moving downward, so he didn't notice it was changing. At the same time, Timmy's back and shoulders broadened and he was getting quite uncomfortable on the couch, but the movie was so good to pay it any further attention. While he put his hands in the bag of chips, his arms were lengthening and thickening. Even his hands looked bigger and bigger each time that he put them in and out of the bag of chips.
Right now, Timmy looked just like a big and beefy version of himself, but it changed when body hair started to spread through his skin. From his meaty and going through his tree trunk legs, his belly, chest, arms and hands, he got a decent amount of blond curly hairs. It was so thick in several places that it looked darker. His baggy pants were now tightly around his legs and they barely covered half of his thighs. His t-shirt now seemed printed on him and ready to burst in any moment.
He coughed a little thinking he was eating chips so fast, but actually it was his Adams apple growing up and his voice deepening in consequence. Facial hair was finally appearing on his jaw and cheeks, and his scalp hair was thinning out and falling down at the same time. Now, he actually looked like his dad except for the glasses that his father use to wear. His vision was blurring a little but he thought he's just tired.
When the climax ended, Timmy stopped paying too much attention to the movie. He felt weird, a little bit numb and very very itchy. He wondered id it's because of the couch but when he tried to scratch one of his armpits he realized it. The seams tore off and a thick bush of nasty curly hairs poked out from the hole. "What the fuck?!!" He shouted and he immediately fell off the couch due to the surprise.
"Ouch!!" He yelled and he noticed that his voice sounded very different, like a man, like his dad's. He managed to stand up, ignoring the meaty and hairy arms and legs for now, until he realizes that he was at least 2 feet taller than before. "What the hell happened to me?!" He shouted with his unrecognizable voice. He took his neck and noticed the prominent Adams apple and the thick beard that grew on his face.
He raised his arms and his other sleeve tore off exposing another thick bush of armpit hair. He was so surprised by the copious amount of hair that he took his t-shirt collar and ripped it off, exposing the pelt of hair on his chest and newly grown beer belly. While his hands moved down through the hefty belly, he noticed that his hair was particularly prominent on his crotch. It was poking out from above his shorts.
Timmy didn't know what to expect when he pulled the shorts' waistband and noticed a bush of pubes way more thicker and prominent than the ones on his armpits. It's like he had a second beard between his legs. He needed to watch it clearly, so he quickly pulled his pants down, but he didn't expect a huge pair of hairy balls and a fat salami jumped out as well. He can't believe, he didn't know an adult could be that big down there.
He held a ball with a hand and it felt hefty like a chicken egg. It was a pleasing sensation that started to make him hard. "It can get bigger?!" He shouted when he noticed his dick was getting thicker like a soda bottle. His foreskin was pulling back and then he realized that he was circumcised and he couldn't grow back a foreskin. With his raging erection starting to drip precum he walked towards the full length mirror in a corner.
"I'm dad!" He shouted in surprise and he immediately shot his jizz to the mirror. He stopped moving and his mind seemed blank for a moment until he started blinking again like he had recovered his senses. He looked around like he doesn't recognize where he was. "How I ended up here?" He wondered before he looked at himself through the mirror. "And what the hell I'm doing naked?!!"
With that ejaculation, Timmy's mind left his body and it was replaced with his dad's. He noticed the movie credits on the TV and a bag of chips on the floor. He also realized he has one of his son's shorts and briefs between his legs. They were definitely small for him, but could work while he goes to his bedroom and takes some of his own. He turn off the TV and put the clothes on. It was crushing his nuts but he could handle it for a few minutes.
Meanwhile, Drake was still jacking off after watching his little brother turning into his dad. He saved the video in his computer and he played it again several times until he cummed twice. He didn't expect the transformation will occur that way but he was glad it wasn't just a boring puff like a cheap tv effect. Looking through the cameras he noticed that Tommy was coming out of the bathroom and now Drake was wondering if he should change him too.