Creampied 18-year-old Stranger Girl

I was surprised and didn’t know what to do ,but Mary did. She had always taught me things as I was getting older ,so she decided to tell me what a blow job was. She did make it to the tree and then began yelling at me. She also said that mom and dad won’t be home tonight so go take a shower. “Mary told me she had a handsome brother, and she also told me tonight I will be happy to have a nice cock”. My first time having sex wasn’t the last time with my sister or her friends. I was only 15 when I saw my sister ,Mary, taking a boy into her bedroom. I stroked my cock harder and for the first time cum shot out of it. I didn’t let her have the rope ,I did say I was sorry several times which did make her walk away. Now this was the first time having a girl laying naked over me ,so I tried doing what I had seen in the magazine .