One day me and my sister were alone,we're around the same age.I was 18 an she was 16,she had just hooked up with this boy form school and all.She had been asking me all these wird quistions about sex and stuff like what was a bj,doggy style,and getting eatin out. So the wheels in my twisted 18 year old mind went into hyper speed, cause I'd had always thought she was super hot she had a nice round ass and about a size DD breast and she always dressed real sluty. So my plan was to be her sex Ed teacher. So later that day I told her that I could help show her how to Plz her man,so she agreed to it my cock got so hard, hader than ever before.So we waited till the time was right when our mom an dad went out of town on vaction for like a week.Oh and you can bet ur pants as some as they were gone we got to work.At first we took a long hot shower and let get use to seeing a big hard cock cause I was about 9 1/2 in and about an 1 1/2 around, she was like a kid in a candy store.