Whenever I started puberty my mom knew I would start masturbating, so she came up with the rule that as long as my door was closed, I could do whatever I wanted and she wouldn't say anything about it. This worked out well until one Saturday morning.
I was laying in bed feeling pretty horny, so I got naked and got one of my magazines from under my bed. I was stroking away and starting to precum when all of a sudden my door opened and my mom walked in with a basket of clothes to put away. We both froze for a second and stared at each other, but she then started to put my clothes away. I laid there for a few seconds not knowing what to do, but the longer I sat there the hornier I got being naked in front of her. I then thought that she knew the rule and it was my room, so I went back to stroking myself. I knew I was going to cum pretty fast so I rolled over onto my back, and a few seconds later I groaned and hot cum shot all over my chest and stomach. I laid there catching my breath, and when she was done she glanced back over for a second and walked out, shutting my door. I was still incredibly horny, so I started masturbating again without even wiping off. After I came the second time, I got dressed and went downstairs. She didn't say anything about what she saw then and she never did, but after that she would always knock first.