You can feel your ears pulling to the top of your head as you continue to push into your mother. The fact that you are mating with your mother had disgusted you moments ago but now it only fuels your desire.
You see your nose and mouth push out into a muzzle as your balls tighten. A few more seconds and you will explode into your bitch as you become a dog. Your tail falls out as you climax.
"Very good my son." Your mother has changed back to her human form. "No wonder you get so many girls."
You can smell your mother's arousal as she thinks about what you have just done with her. You walk over and lick her crotch. She moans but then pushes you away.
"We have work to do, before we can have another go at it. Cal tells me that he got both the collar and the dildo from his sister's room. That means that she must have experienced this power. She would make a powerful addition to our pack. I have chosen you to bring her into our pack my son. I will keep their dog busy while you quietly replace him. Cal has said that he witnessed his sister mating with their dog so getting her to submit to you should not be a problem."
With the plan in place, you follow Darleen and Cal out to Cal's car. Darleen lets you and Cal into the back seat and then drives off...