Rick wakes slowly, warm soft sheets beneath him the soft skin and heft of his wife atop him. He smiles warmly, rubbing his body into the sheets, feeling his muscles stretch and bones pop from their resting spot. His mind slowly wakes, trying to think how he and his wife came to lay like this, his cock still embedded within her. His mind jogs through the last things it could recall, groggy intermittent jarring images. His mind notes that his wife must have gained a few pounds. His hand lowers to investigate. Fingers touch against oddly firm shoulder muscles. He recalled smoke, discomfort... no pain. His hand rolls down his wife's chest. Hair? The mind recalls Brandon screaming, a beast, pain!
Rick startles fully awake, looking down at his stepson asleep across his chest. Rick cries out, shocked. Brandon wakes, startled. Brandon looks up, seeing Rick beneath him. He screams and jumps from the bed, caught for a moment disgorging himself from Rick's cock.
He stand and spins, staring down his naked stepfather in horror. Rick stares up at his stepson, returning an equally horrified look. Seeping down Brandon's gut are over a half dozen lines of congealed cum. Brandon grabs and covers his package and runs towards the bath in the hall. Rick hears the door slam, leaving him alone to clean himself.
Looking down his body, he notes many new differences. His abdomen was taught, six impressive mounds bounding down along it. His chest was barreled out, muscled immensely. His legs were thick like trunks, his arms muscle knotted limbs. He stood and moved before his full length changing room mirror. Even against the slowly surfacing memories, he couldn't help but feel proud. He felt, he looked, virile. His limp and glistening member, dangling at mid-thigh length and gaining quickly with arousal, only affirmed it. He felt younger, stronger, bigger, and, from first glance, it was certainly true.
While he admired his naked body, his mind recalled the night fully. He remembered being... used by that beast. He remembered the pain he felt, the transformation. His memories grew hazier after that, but they slowly surfaced. The lust, driving him to Brandon's room. He Pushed himself into the room. Lying on the bed was Brandon, not the creature, but his human stepson. Brandon looked tired, then, seeing Rick, frightened. He had grabbed Brandon. He forced himself inside Brandon. Then... then Brandon changed...
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Brandon sat on the bathroom throne, swabbing off the semen across his gut. He recalled moving into his room, after... after raping his stepfather. He felt himself change again, reverting to human. He laid on his bed exhausted, then the door opened, some enormous bull creature forced its way into his room. It grabbed him. It impaled him onto it's enormous cock. It fucked him. Then, then Brandon recalled feeling aroused. The beast rolled them both onto the bed and laid beneath him, fucking upwards into him. As he was repeatedly ravaged by the beast, he felt himself yearning for more. The lust welled in him uncontrollably. The room dulled in color, and he remembered transforming again, changing to the beast, allowing, wanting, himself to be fucked. The bull burst deep inside him and calmed, but he remembered continuing to ride the softening cock, stroking himself furiously. He quickly reached his plateau and shot repeatedly across his chest. He fell back exhausted against the bull, only... it wasn't the bull any more. It was Rick. Rick was resting beneath him. Brandon felt his body changing back, but he fell asleep before it could finish.
Brandon reached beneath. His finger came against his hole, and he felt the slick familiar substance, the same he had been cleaning from his chest. His eyes welled with tears, and he quietly sobbed for the depravity he took part in last night. He mourned that lost bit of innocence. He cried harder, because he realized how much he enjoyed being like that and that, as much as he wished to deny it, he furtively wanted it again.