As Jason stared at his older brother on the floor a thought came to his mind. "Why should I give him his spunk back; He was the one that tricked me into coming here in the first place.." He looked at himself in the mirror on the wall. He was still the same height he was before, but that was about all that hadn't changed.
His looked completely different with his newly sprouted hair, and his now defined muscles. Jason flexed his arms, "Jesus" he stuttered. A feeling of Ecstasy came over him. Jason looked down at his soft member. He remembered how just earlier this day that it hard had not even been a quarter the size it is now. His member began to swell at the thought of it. "God I'm hot" Jason said to himself while grabbing his dick. It felt so different than before, more sensitive almost. It felt good..
"Why should he get to be big?" He yelled staring at his brother again. At that Jason walked over to Matt and picked him up (he could hardly push his brother before) and set him gently on the metal table in the corner of the room.
From the looks of it his brother was in the early stages of puberty. There were small hairs protruding from the base of his legs, and a few hairs coming out from his armpits. His penis was obviously larger than it was a few minutes prior, but still not even a third the size of Jason's. On Matt's tall body it seemed ... wrong.
Jason bent down and put Matt's dick into his mouth. It was very smooth and small, it barely hit the top of his mouth. It quickly got hard as Jason slowly massaged it with his tongue. He wondered if Matt could feel this passed out. Was he enjoying it? Jason picked up the motion, he didn't want his brother waking up in the middle of it.
Jason continued giving head to Matt for another five minutes. "Jesus!" Was there any jizz in there? Finally his brother came, and Jason was sure to catch every drop. It tasted disgusting, and he did not enjoy it in the least bit, but he swallowed.
At that moment Jason felt a surge of energy, it was as if a thousand needles were being stuck into him at once. He did not faint though, as he had previously; He wanted to see it happen.
He watched as the little hair Matt had attained just earlier receded and appeared on his own body. Jason's bush was now the size of any adults. He felt himself getting stronger,as Matt's muscles shrunk.
Jason couldn't help but feel slightly sympathetic for his brother. He was being left with nothing but his height and his mind. But as Jason soon found out, he was only right about one of the two. This time the change was different, Jason was getting taller as well. It was an awkward feeling, as if he was going up a very slow elevator. Jason soon towered over the table where his much shorter brother lay. He estimated from how tall he used to be in the mirror that he had grown a good foot, putting him at 5"11.
What he saw in the mirror was amazing. His was far more proportional now than before. His arm muscles were all bunched up into a small arm, they were now spread out along a longer adult sized arm.
He felt like a man, he felt ready to be his older brothers new big brother...