Play along. It's MOSTLY teasing.

Taylor looked at the bulging front of Zack's shorts as he stood beside her bed. She opened her eyes wide and blinked meaningfully at her brother. "So?"

"So?" Zack said.

"You planning on sticking around or are you gonna take that back to your own bed?" Taylor asked.

Zack blushed. "Um. Oh."

Taylor laughed. "I gotta say I'm more than a little curious about what made Ashley flip over my nerdy little brother. I kinda figure it's what's in your shorts."

"Oh," Zack said.

"Show me?"

"Really?" Zack said.

"Yah really," Taylor said.

Zack pulled down his shorts. His substantial erection sprung up from a root nestled in his dark brown pubic hair.

Taylor grinned. "You've got a nice one there," she said. "Nothing at all to worry about. Well, unless..." She laughed.

"Unless what?" Zack said.

"Unless you wanna put that in somebody's butt," Taylor said. She tilted her head. "Hmm. Yeah, it'd still work, you're not THAT big."

Zack giggled. "Oh. Thanks," he said. "Wait, how would you know?"

"Ha ha," Taylor said. "Guess."

Zack's eyes widened. "Really?"

Taylor laughed. "Go to bed!" she said.

"Aww," Zack said.

"No really, go give yourself some nice dreams, and tell me the rest tomorrow," Taylor said.

"But..." Zack began.

Taylor brandished her forearm-long vibrator at Zack. "Out! Shoo! Leave a girl in peace!"

"Goodnight," Zack said. He pulled up his shorts and headed back toward his room.

"Goodnight!" Taylor yelled through the door.

The walls were thin. Zack could hear the buzz of her vibrator and the squeak of her bedsprings as she shifted with the sensations.

When he heard his sister's cry of release, Zack spurted through his stroking hand, covering his belly with warm seed.

"Goodnight, Taylor," he whispered to himself. He mopped himself with a wad of tissues and rolled onto his side to go to sleep.

He dreamed he was back in the cabin.