She knows I watch porn regularly, and that I masturbate looking at her pictures. I know what brand of undergarments she loves (along with the exact si...es), and that she likes to be fucked in the doggy style. So, I was only being reserved for the other staff members that would walk around.A few minutes later I could not take it any longer. I got up, walked to the door and closed it. I turned away from the door towards her. She looked at me, “What are you doing?” She asked.“I need to do something. Emily ripped the white cotton bra right off of her sister, and tossed it onto the floor. Rebecca’s large breasts spilled free and bounced up and down twice. Emily sucked in deeply at the sight of her sister’s breasts. Then, a sly, wicked smile crept across Emily’s face. She leaned down, and placed one hand behind Rebecca’s head, and brought her face up. Emily and Rebecca began again to make out, their tongues intertwining for the second time that day. Rebecca tasted the sweetness of Emily’s. Her legs, like her arms, were long, slender and gracefully muscled. She turned sideways and stuck out her posterior, noticing once more the immaculately rounded curves of her cheeks, the object of many disappointed artists, photographers and would-be lovers.As long as she could remember she had greatly admired the female form with its elegant curves, quite unlike the repulsive masculine sharp angles and bloated limbs. Her face twisted in disgust at the mere thought of men as she shifted her. I wasn't about to chicken out now so I said OK, but it had to be my own clothes and few other guidelines. I thought I was pretty safe. How bad could it be? When I got out of the shower this morning she had my clothes laid out for me on the bed. I felt my nipples perk up and a flush of warmth between my thighs as I saw what I was about to go to work in. She had dug out a short, very low cut, sleeveless summer dress. I had casually mentioned a couple of weeks ago I didn't wear it to work.