Naive step-sis
A step-sis who acts like she doesn't know you're about to give her the biggest blow job of her life. Then she says she knew all along and laughs like a hyena.
My step-sis cried when I told her I was going to kiss her. Then she said she knew I was going to do that the whole time.
My step-sis pretended to be shocked when I walked in. She wasn't. She was just trying to make it funny.
My step-sis said she didn't know I was going to sneak into her room. She lied. I knew she knew.