I unzipped my jeans and tugged them down a little, slipping my hand into my boxers. Nowhere near as big as the guy positioning his cock at her pink little hole (I loved that picture, her fingers spreading herself open for him like that. Gah! Did girls do that?) but respectable enough-nice and thick, and most definitely stiff. She did it for me, every time. I started masturbating, my eyes skipping from the wet pink of her cunt to her thick, dark pink nipples. I spent some time there, wanking away and staring at the slit between her legs. She spread it open with both hands, and there was a little hole there, right where I wanted to slide my cock, a small dark hollow leading to heaven.

I got myself good and worked up before starting to turn the next page, because it was my favourite, and it was the image I always came to-her arse up in the air, his cum sliding down her arsehole and cunt. I was looking forward to that image, still staring between her legs. I only stopped for a moment, breathless, to turn the page, and I saw something that made my cock jump and my heart race. There was writing in the margin, near the page number. An arrow toward the girl (God, look how that thick cum slid down that pink slit!) and the words, “She looks like me.”

That was Dawn’s handwriting-the fat, curly letters, the heart over the “i.” My sister had been looking at my porn? Why, I wondered? If she wanted to get me in trouble, she could have taken it to my mum. Instead, she just wrote in the margins. And what she’d written! I flushed. I knew the girl looked remarkably like my sister-the dyed blonde hair, the full body, the mischievous eyes, the slanted smile-that was Dawn. Was she just making an observation? Was she implying that I lusted after her?

I didn’t have any more time to think about it. Someone was knocking on the shed door! I stood, tucking my cock back in and zipping up, shoving the magazines back under the pile of boards.