The 18 years old girl choose de to pick the doggy biscuit "it will be very interesting"
She picked up the bag and took it to her bedroom. On the way she dropped a biscuit without noticing it. When she was arrived on her bed she started to eat a bit more than the half of the biscuit. 2 minutes after she eat it she starts to felt the changes. First the 18 years old girl felt her ass and boobs expanding making her wanting to touch herself. She lied on the bed, face to it, starting to touching her wet vagina because of the heat she was going into. After not even 30 seconds she felt a furry thing touching her vagina, her tail had grown and she starts moving it without noticing it. As she touches her already big boobs she felt four more breasts starting to poke out off her belly. She started touching them making her feel hornier. She stops to take a look in the mirror but when she her changing body she became even hornier than before, her vagina was dripping wet, her doggy tail was shaking furiosly, admiring her transformation, her tongue stick out of her mouth and she starts to pants heavily. She dropped on the ground and can't stop pleasuring herself as her ears starts getting all furry, shaping into those of a dog. She was now having two blond dog ears dropping on her eyebrows. She started to feel her feets becoming paws. the big part of the change comes here. She starts having an orgasm, she starts growing blond fur on all her body , her bones reshaped preventing her from getting up. She was now more a dog than an 18 years old girl, even if she keeps all the perks of a young woman. Her vagina starts to change into one of a dog, giving her pleasure while changing. As a final change she grows a doggy muzzle, she still got her pretty face but with dog's traits.
After the change's done the girl felt even hornier than before. She maybe still got her brain, the heat was not letting her have logical thoughts. She thought of something that could help her, she was having a dog, a male, one that could help her, satisfy her, breed her. She slowly start to want it, can't think about another thing than his cock. She starts to bark while getting downstairs to call her dog , her mating mate.