"Hallie Gwen having a blast with Sofi, she seemed a little scared at first but... ohh who im kidding, she was very scared of that striped dong! At first it wasn't so big, but then Hallie said something like "Let's make things a little more interesting..." and then that big striped thing started to grow and grow inside Sofi and well, yeah that's how she ended up!"

BTW, the black and white striped penis is in fact her panties that are under a "spell". She can make her panties transform into a dick of any size she wants.

^^GBlastMan's comment^^