To start off I am sixteen and masturbate regularly. By regularly I mean once a day if not more. I live in a house with my Dad and step-mom and also have an older step-sister, she's 23, my step mom is hot, she is like 43 but looks incredible! My room shares a wall with their's and late at night I can hear them having sex including all the moans and groans. I love to hear her moan and scream in ecstasy. I masturbate to it everytime I hear her. This story is about one night when something out of the norm happened.
It started off as usual, a couple of laughs then silence, then some talking in low voices (that they think I can't hear) then some silence then I can hear my Dad groaning so I assume my step mom is giving him a blowjob or handjob or something to get him so excited. At this point I unzip and get ready for the noises that I love most to start to happen. I started to hear the bed creak very slightly and also started to stroke myself. Five minutes or so into them having sex she starts to enjoy it more and more and is moaning softly but enough that I can hear. I am really liking this and am now fully erect, this is when something unusual happens, the silence of the night (minus the sexual acts) is broken by a phone call. It scared the crap out of me and I heard my dad whisper scream WHAT NOW, so they stopped. I didn't know this at the time but my step-sister was really drunk and needed a ride back to her apartment.
So my dad went to get her. There was some conversation that I couldn't make out and then I heard the car start and drive away. Minutes later I still had a raging erection and went to tend to it with some hand lotion so I could get to sleep. I crept to the bathroom so as not to alert my step-mom. Once inside I grabbed the right amount of lotion and went at it. I am completely naked stroking my six nearly seven inch erection, moving along nicely now. Fifteen minutes have passed since my dad left and I hear a slight moan. I nearly came right there! I turned out the light and went down the short hall and looked into the master bedroom, there I saw her masturbating using her two fingers inside her and her other hand is taking turns rubbing her clit and nipples. I am seconds away from coming after seeing this. I look down at my dick and it had to be a half inch to an inch bigger then usual! She started moaning loud and I had to come and had to time my groans with hers so she wouldn't hear, it worked and she didn't hear me. I sat in the hall on my knees spurting string after string of cum into my hand and then I rubbed it into my stomach and penis and continued to view the show. I soon got another erection but didn't stroke it. I just let it grow and enjoyed the feeling.
She was now really near climax and moaning loudly, it seemed very loud because I usually hear her through a wall but in this situation I was about ten feet from her. I was dripping a steady stream of precum and knew with a few touches I would ejaculate once more. I did so because I knew it would never go down if I didn't, unfortunately this time it was very powerful and I groaned very loudly. She looked towards me slightly as she was subsiding from her climax. She couldn't see me due to the darkness of the hall but I know she knew I was there. I ran silently to my room and pretended to be asleep. I heard her walk to the door and look in seconds after I did. I could feel her eyes on me, but to my suprise she walked back to her room. I fell asleep about an hour later.
This happened two nights ago, she hasn't said anything yet, but there has been an awkward tension between us. She is home alone with me in two more nights for a stretch of three days, my dad is going to be out of town for work. I wonder what she is going to do. I am both scared and excited. If something good happens I'll write again but don't get your hopes up. I certainly don't have mine up!