Sucking and stroking me didn’t get me off either.The doors to the room burst open, and I felt tiny fingers on my dick. They couldn’t even get half...way around it, but a few strokes and I was firing get after jet of cum out until I felt my balls emptied of sperm. I didn’t get to see who did it, but they did feel familiar, somehow.“ARLENE! COME BACK HERE,” I heard a woman screaming as she was running toward this room. “You don’t run off like that and into anywhere you don’t know, especially. I was speechless. I didn't know what to say. I didn't hear here coming at all. So I just stood there, staring at her with a huge boner bulging from my pants.“Show me what you have.” she commanded me. I stood like a stone and didn't budge. “Show me.” she said as she approached me. She stopped within arms reach of me and grabbed my shirt to pull it up. I attempted to fight it but my pants were not buckled and fell to my ankles. I reached for them and let go of the panties and playboy. My sister. Raising up on my arms and looking into her lust filled eye, I stroke deep and hard, matching her pace. Her legs wrap around me pulling her up to bring me deeper with each thrust. The angle causes the head of my cock to rub hard against her g spot and increase the pressure on the sensitive head of my engorged cock. Our moans grow louder as we both tense up, fucking wildly as her muscles tighten on me. My balls tighten and pump my hot seed through my cock and into her belly. Simultaneously, she. .." I know what you meant." First day as a woman and you're on your period. Great." I am NOT on my period, you jerk!" You're on something."The conversation didn't go much further than that. Mostly it was slammeddoors and the shouting of distant threats. By the time we got tosomething resembling an adult conversation it was noon. I'd planned onstaying in the bedroom until he headed out, but a certain something hadbeen detrimental to my resolve. It had been there since I'd gotten overthe initial.