Roger ran all the way home from school arriving out of breath. His cock had been hard most of the day in school, sitting through class after class with teenage girls all around him. Short skirts. Tight sweaters. It was tough being sixteen with all those sexy young things all around him all day. Roger wanted to get home before his sister did. Her junior high school let out thirty minutes later than his high school did. He would have at least thirty minutes to masturbate before she got home.

Roger went to his bedroom, firing up his computer. He stripped naked while the old machine went through it's tedious start up procedure. When the computer was all the way up Roger started a slide show program pulling up about two hundred photos from a hidden directory. In random order the slide show would put, on his large monitor, various photos of naked women. Some were shown by themselves but the majority of the pictures showed a man and woman having sex in many different ways. His favorites were the ones of the woman on her knees sucking on the men's large cocks. It seemed that all those men had bigger cocks than young Roger.

Roger laid back on his bed with one hand gently rubbing his hard cock while he watched the photos glide by at exacting fifteen second intervals. Every now and then Roger would glance at his bed side clock wanting to make his daily masturbation routine last as long as possible before his younger sister came home. Roger's sister Mary was just a year younger than himself. He had to admit that she was cute as a button. Her bottom was rounding out nice. Her boobs had begun to grow to a size that their mother had bought her a bra.

On the monitor was a young oriental woman with just the head of a large prick in her mouth. He could see the woman's saliva shining on the man's cock. The youngster dreamt about getting his first blow job. Just the thought of a girl's soft mouth on his prick almost made Roger cream. The slide show went to the next photo. It was a big black man sticking his cock into a small blonde woman's pussy from behind. It had taken Roger weeks of scavenging sites on the internet to find just the right photos for his collection. The next shot was of another blow job. This time a young girl was sucking on the penis of a man old enough to be her father.

A scuffling noise caught Roger's attention. He looked quickly around the room seeing nothing at first.

Then he noticed that his closet door was ajar just few inches. He usually was pretty good about keeping the door closed so his mother wouldn't yell at him. Sometimes in his haste to get to school in the morning he wouldn't get it closed all the way. He glanced at the mirror on his big dresser. The mirror was at an angle where someone in the closet could get a good view of his bed. He could see the shine of Mary's eyes as she crouched on the floor of his closet, not quietly enough, spying on him.

His hand never left his cock. It remained hard. The thought of his sister watching him stroke his prick excited him. The photos continued to appear on the screen, being replaced every fifteen seconds by another erotic photo. "I can see you Mary. Come out of the closet if you want to watch. I don't mind."

After a short pause his sister sheepishly came out of the closet. Roger patted his bed. "Come sit here so you can see better." Mary slowly approached the bed never taking her eyes off of her brother's erection. Roger was still moving his hand up and down on his stiff penis, deliberately and more slowly than before. He wasn't very big but his five inches looked large to Mary. She marveled at how hard it was. She wished she had her own prick to play with.