In my last story I mentioned I had a s****r, well she is my step s****r. This story happened a few months after the incident with my mom. I was 14 and s*s was 17.
So, I was doing my normal thing and spying on my mom while changing. I was masturbating and my s****r caught me. She started yelling mom, which was not cool. Long story short, mom ground me and took away my computer.
I was so mad at my s*s. I thought of a plan to get her back. I was going to secretly cum on everything she has. I was going to start small. So the first thing I came on was one pair of panties.
The next day after school. I got home before she did, she did sports. So I went straight to her room. As I opened her pantie draw my dick started getting hard. I picked out a pair, that looked to me, that she wore a lot. I pulled my dick out and d****d her panties over him and started stroking it till I burst. I rubbed the crotch area together to make sure the cum was spread all over and so it wouldn't be obvious. I folded them the way she had them originally and put them back and waited.
She got home maybe 2 hours after I came in her undies. I heard her get in the shower. Normally this is when I would spy on her to see if I could see her naked. But instead, I went to her room to see if she grabbed the undies I came in. And yes it was. I was started to get excited. I thought, she is going to put my cum right on her pussy. My dick is hard by now, so I grabbed another pair and came in them also.
I went back to my room and waited. When she got done in the shower and went back to her room. I went to the dirty clothes to make sure those went there and they weren't. I went to her room to ask her her day was. I didn't knock I just waled in and she had a shirt on and was about to put her shorts on, but I saw the undies with my cum in them. I could see a little bit of damp spots on the crotch. She yelled,"get out you little perv." I guess she saw the hard on in my shorts. I told her I was sorry and I wanted to see how her day was. We chatted for a few mins and then I went back to my room.
Over the next month. I picked out random things to cum on. More undies, bras, back for her shirts, in her shoes, on her pillows, her hair brush, tooth brush, I even went as far as carefully opened some pads and came in them and closed them up and put them back. I never heard anything that she suspected something.
So, I thought of one last thing to do.
I hide in the bathroom before she got home for soccer. She did like she always did, went to her room to get clothes and then the shower. She likes to play music in the shower, so that was a plus for me. I came out of my hiding spot, dick hard. I grabbed her undies and wrapped them round my dick and stroked as I caught a nice view of my naked step s****r. I busted a huge load of cum in them. Put them back where she had them and went back to my hiding spot.
After her shower I asked her if she wanted to play halo with me. She said yes and we played till dinner time.
Till this day she has never said anything to me and I still cum on something of hers every time I go visit her.