Breast Friends

"I wish that the two of you were my left and right breasts, and could communicate with one another telepathically."
The stone flashed. Jon's clothes disintegrated around him, leaving him naked. He felt a tremendous crushing weight, pulling him into a fetal position. His flesh felt warm as his arms and legs melted into his torso, leaving him a ball of flesh with a head attached. His neck cracked as his face became flush with his body. The hair on his scalp fell out, leaving a small pile on the floor. He glanced over at Karyn, who appeared to be in a similar state. The look on her face was one of desperation. As he watched, her facial features were absorbed as her face became a giant nipple. He felt his own face twisting in a similar way, but oddly could still see. The world began to shift around him as he and Karyn shrank to the size of normal breasts.
The transformation complete, Jon felt a giant hand wrap around him as Sarah lifted him up and held him in front of a full body mirror. She had him in her right hand; in her left, she held Karyn... or at least, what was left of her. Jon could see a few familiar features on her new form: a small mole that had once been on her left arm, and a butterfly tattoo that had once been a tramp stamp above her buttocks. As for himself, he could make out the shape of an elephant-shaped birthmark from the bottom of his left foot. Otherwise, there was nothing to indicate that either of them had ever been human.
"Ooh, you two will look FABulous on my chest!" Sarah removed her blouse and bra, revealing a flat, featureless chest where her old breasts had been. She then held Jon and Karyn against her chest and pressed. Jon felt a warm, tingling sensation where his butt had once been, which soon subsided. Sarah let go, and he felt himself just... hanging. He was a part of Sarah now. He watched himself rise and fall on Sarah's chest as she breathed, realizing that he would never again have to respire. He got all of his oxygen from her circulatory system. Her blood was flowing through him.
He was just a breast.