Dad's Camcorder Ch. 04

"Maybe I should ask you to help me with my homework," I said.

She was breathing a little harder, and wouldn't look right at me.

"What homework do you have?"

I grinned. That was a great question. She should have got all pissed and disgusted and yelled at me, or at least run away. But she didn't.

I unzipped my jeans and pulled out my long, thick erection. Her head turned and she stared straight at it.

"What class is that for?" she said.

"Biology." I put my hand around my dick and stroked it slowly.

Mary nodded, never taking her eyes off my dick or my hand.

"What do you have to do?" she said.

"We're studying the effects of sperm on young girls."

She nodded again, as if the scientific study appealed to her intellect.

"What do you want me to do?"

I shrugged. "You can help me get the sperm to come out."

"I'll try," she said, and closed her math book.

"Cool. Give me your hand."

She held her hand out with the palm open, facing up. I took her hand, moved it toward my cock, and closed her fingers around the shaft. I moved her hand up and down slowly, just like I was doing myself just a moment before. She squeezed and I moaned.

"Is this how you do it?" she said.

"Yeah, that feels good."

"If I keep doing this, is it gonna make your sperm come out?"

"Yeah. No doubt."

I leaned back on the couch and let my legs spread wider. Mary kept pumping and leaned closer to my cock. She was staring at it and I was staring at her. It was hard to believe this was my cute little sister jerking me off. The tip of her tongue stuck out between her lips and she looked like she was enjoying it.

"Go a little faster," I said.

She smiled at me and her hand pumped faster. I groaned and closed my eyes. She may have been my cute little sister, but her hand felt really good.

"Dorsey?" she said.

"Yeah?"

"What makes it get so hard?"

"I don't know. It just swells up and gets hard," I said.

She looked puzzled, though. Her hand continued to move up and down.

"Is there a bone in it?"

"I don't think so."

"Then why do they call it a boner?" she said.

"Who calls it a boner?"

"Peter. He showed me his thing last week. He called it a boner."

I could only stare at her. Was she telling the truth?

"What did you do when he showed you his ... boner?" I said.

Mary shrugged. "Not much."

"Did you touch it?"

"Only for a second. Mrs. Poole nearly caught us."

I was shaking my head. What else did I not know about my sister?

"Dorsey?"

"Yeah?"

"Your boner is so much bigger than Peter's," she said.

I waited for her question, but it sounded like she was done.

"Yeah?" I said.

"I mean, aren't all guys the same size and stuff?"

"Most guys. But not me," I said.

Her eyes brightened. "Really? Why not?"

"I don't know. I got lucky I guess."

She didn't speak for a while. Her hand had slowed down, so I put my hand over hers and got her going faster again. She was concentrating very hard, and in her eyes was a look of determination. She pushed me beyond my control.

My body tensed, and I was going to cum very soon. I forced myself to relax, and that only intensified the sensations. It built and it built, then seemed to hold off for a second before I exploded.

I think I must have cried out. My body convulsed with spasms and my ass lifted off the couch. The first, most intense shot of my orgasm sailed across the room and landed with a splat on the carpet near Dad's stack of newspapers. Mary squealed, and I had to look at her to see if she had been frightened. She wasn't. She was smiling.

More and more of it pumped out, one shot after another. It spilled on the carpet between my feet, on the sofa, on Mary's hand, and some of it got on her math book.

Finally, I slumped back on the couch, panting and flinching with the leftover spasms, like aftershocks, that shot through my body. Mary kept pumping my cock, which was finally going soft, and staring at the cum that covered her hand.

"How did I do?" she said.

"Great. I think I'll get an A," I said.