Brushing My Knots Out

I first learned to masturbate when I was 13. At the time, I shared a room with my sister, who was two years older. It was hard to find privacy sometimes, so usually I would either hurriedly rub off during the day when she wasn’t around or wait till late at night when I thought she was asleep. Once in a while I would hear her doing it or see her hand moving, which usually set me off as well, but she never said anything about it and I naively assumed she had no idea I masturbated too.   Eventually I graduated from just rubbing my clit to occasionally fucking myself with the handle of my hairbrush as well. I usually only did this when I had the room to myself because it was a lot more obvious than just discreetly teasing my clit to a quick orgasm, but one night I was super horny and really wanted something inside me. When I was sure she was asleep, I pushed the covers off me, slipped my hand under my T-shirt and played with my boobs for a while to get myself going, then I pushed my panties down below my knees, spread my legs as wide as I could and started doing myself with my hairbrush handle while I rubbed my clit in little circles with my other hand. As I got more and more horny I started going faster and faster. I could hear the little squishing sounds as the hairbrush went in and out, but I didn’t care. I really needed to cum. Then I heard her burst out laughing and she said “Brushing your knots out T?”  I looked over and saw her looking straight at me. I froze for a second, my hands still buried in my pussy, then answered “Yeah, sometimes they’re kinda hard to get out...” She laughed again and said “Don’t worry, I’m just messing with you. I’m gonna put my earphones in and listen to some music. You go ahead and finish up, it looks like you’re really close.”  As soon as she put her earphones on and turned away, I started doing it again hard and fast. It only took a couple minutes before my whole body shuddered and I came really hard. After I finished cumming and my body calmed down, I wiped up, pulled my panties back up and turned the lights on to let her know I was done. She rolled over, took  her earphones out and smiled at me. “Wow, you must’ve really needed that. Don’t be embarrassed. I do it all the time.” I blushed and said “Yeah, I did. Thanks. Um, do you need to do it too...?” She shook her head. “Nah, I’m good. But next time I get really horny and need to rub one out, I will. And the same goes for you. I won’t watch or anything.” With that she rolled over and went to sleep. After a few minutes, I did too.