"It's a beautiful day to go to the beach, don't you think so?" Madison said as she started to walk. "I could drive us there but that won't be fun. I prefer you carry me in your arms."
"M-my arms?" Ryan stuttered as she jumped on him. He instinctively grabbed her but he was afraid she would be too heavy for him. Surprisingly, with his new adult strength, his sister was way more light than he expected.
Ryan walked for a while only with his tight underwear hiding his almost obscene erection. Madison wasn't too heavy but he was getting tired and ashamed. People were watching at him and despite he tried to ignore them, it's too humiliating for him. He wanted to cry, to run away and hide under a rock but he can't. He was at his sister's mercy.
"I'm bored." Madison suddenly said. "Put me on the ground." He obeyed and carefully placed her on the sidewalk. "The bus is coming. I will go in there but you'll go jogging." Ryan reddened because he knew that his dick would be swaying and he can't do anything about it. "You will fart continously and if you try to stop you will shit on yourself. Oh, and to make it even funnier, you'll have extra reeking armpits." Ryan can feel the bushes under his arms thickening. "Have fun!"
Ryan watched his sister taking the bus and almost immediately he started to jog. His legs were moving by their own and he shamefully realized that his dick was swaying side to side like he predicted it. However, he knew the worst was coming when he felt a gurgle in his stomach and seconds later he released a loud and nasty fart from his hairy butt. This is going to be a long trip, he thought.