My blind stepsister asked me to help her with her Tantaly male sex doll

My blind stepsister invited me to her bedroom and asked me to help her with her Tantaly male sex doll. Watching my stepsister ride the Tantaly male sex doll gave me a boner, so I shoved my cock inside my stepsister's pussy and fucked her from behind. I also fucked my stepsister’s ass while she rides the male sex doll.