My Stepsister's Inner Slut

It was Saturday afternoon and my sis Aidra was at home studying instead of hanging out with her friends. I start bugging her about her nerdy ways and how shes never had a boyfriend. Since our parents werent home I went to get some for her. After it she mellowed out and it wasnt long until we were talking about sex! The kicked in fully and I fingered her and she sucked my cock! The next day I surprised Aidra after a shower and I finally got to fuck her tight pussy! We took it into the bedroom where I pounded into her until I came inside her! Fast forward a few more days and Im feeling horny in the morning. So what do I do? her up to fuck! We fuck one last time and I finish in her mouth!