My sister turns 18 and asks me for a special gift.

When the girl entered his room that morning, he couldn't help but feel his member hardening under the warmth of her small body. She looked at him delighted and giggling at his reaction and the day had come, it was her 18th birthday and she was more than ready to claim her favorite wish. There was no escape and he knew it, he had promised her three years ago that he would teach her everything he knew about sex when she turned 18, he didn't ask to risk ruining everything, she was his favorite sister and he wanted to protect her from the world, no matter that the only way to do it was to condemn himself.