I am 18 and a senior in high school. My brother, Eric is 14 and in eighth grade. This happened a few weeks ago. I was having a horrible day at school and I called my mom and asked her if I could leave early. She agreed and told me that Eric would be at home because he stayed home today with a migrane. So I left school and drove home. Once I got home I stopped in the kitchen to grab a bottle of pop and a few cookies. Then I headed upstairs toward my room.
On my way up the stairs I began to hear soft noises. I paused and listened closely. There was no mistake about it, it was Eric and he sounded like he was jerking off. I had to walk past his room to get to my room. I told myself that I wouldn't look as I walked by his room if the door was open or cracked, and I proceeded up the stairs and headed down the hall. Of course, as I passed his room I looked. I couldn't stop myself. And boy did I get an eyeful. There was Eric on his bed, spread eagle, with a pair of my panties pressed up to his nose and mouth and his other hand was working away on his dick. I guess I accidentally gasped because he looked up and started freaking out.
'Why are you home?!?!' He screamed, as he jumped off his bed and covered himself with a shirt.
'I was having a shitty day and I called mom.' I explained, trying to act like nothing out of the ordinary was happening.
'Oh...' He said.
'Yeah...' I replied.
'Please don't tell dad and mom about this.' He begged me. I could see that he was about to cry.
'I won't. Just please puy my panties back when you are done.' I told him.
'Wait, you don't care that I take them?' He asked.
'No, as long as you put them back in the clothes hamper when you are done.' I said.
'Are you serious???' He asked. His face lit up.
'Yes. Everyone masturbates. And lots of guys use panties.' I told him. I had dated a guy before that liked sniffing panties.
'You do it?' He asked, amazed.
'Masturbate, yes. Smell panties, no.' I giggled.
'You? My sister?' He asked.
'Yes! Why don't you believe me?' I asked.
'I don't know, because you are my sister. Like I know girls do it, but I never thought about that YOU might do it.' He explained.
'Well, I do.' I said.
'Can I... um... see?' He asked, shyly.
'See me masturbate?' I asked.
'Well, yeah. I mean, we could do it like, together.' He was really nervous. I could tell.
I thought about it. 'Yeah, I guess. But it will be our secret. No one else can know.' I said.
His face lit up and he dropped the shirt he was using to cover himself and revealed his fully hard dick to me. I'm not gonna go into detail about it but it was on the smaller side. Not that that mattered to me. I closed his door and walked over to where he was by his bed. I took off my shirt and jeans quickly. Him seeing me in underwear and bikinis was nothing unusual. I paused shortly before unclasping my bra and letting it drop to the floor. He was staring, but I don't blame him. Then, I quickly slid out of my panties and handed them to him. He grinned really big.
We both sat down on his bed facing each other and slowly began touching ourselves. We were stroking at the same pace, it was very erotic. After a few minutes of stroking my clit, I pushed two fingers inside of me. I moaned. That sent Eric over the edge. He shot his load all over my legs. There was more than I was expecting from him. Shortly after that, I came. It was one of the best orgasms I have ever given myself.
We talked for a while after that. We just sat there naked. We talked about sex and masturbation and all things related. Eventually, it was close to time for our parents to get home, so we cleaned up. He thanked me multiple times. We decided that we wouldn't make this a regular thing but we would for sure do it again. We haven't done anything together since, but I notice him borrowing my panties more often than in the past. And I still plan on getting together again sometime soon.