My only ally in being constantly teased by friends and gradually abandoned by my parents is my sister! I love my kind sister so much! At first, I didn't intend to look at her with a lecherous gaze, but her breasts are just too big! My eyes were glued to her clearly protruding nipples! Before I knew it, I was fully erect! Of course, there was no way to hide it and it was discovered. To prevent me from feeling embarrassed, she gently reached for my penis and tenderly stroked it.