Overcoming the urge to continue fucking the bitch you pull out your dripping cock. The fur on your body immediately begins to recede and you stand up fully erect. The black lab bitch starts shifting too, and in a matter of seconds you see your mother crouching on the floor panting like a dog in heat, wearing nothing but a collar. You feel as though she has some kind of aura of control, and just stand there gawking at her.
"I'm sure you'll get better with practice Mark, I don't expect you to match Cal's stamina on your first try." She glances over at the german shepherd nosing after his tail. The dog notices the attention and proceeds to help lick your cum off Darleen, she not able to clean herself as a proper dog. "This collar taught me all I need to know about this craft, it's powerful magic witches use to amuse themselves after forsaking men. It is contained in a special dildo until the energy of a man releases it into the world."
Your mom is obviously enjoying Cal's affections, you want to yell at him to stop but you have a hard time even breathing through your hushed cries. Cal is now a large german shepherd, his canine dick poking a couple inches out of an already massive sheath. He tries to mount your mom, but she sits with her organ to the floor, holding the happy dog around the neck, his upper half over her extended legs.
"Amorous aren't you, don't worry Cal, I'll let you change me back soon enough". She lets out a moan as Cal's tongue finds her inner thigh.
"Damn it Mom, change him back!", you finally say, but a crack in your voice shows you have no power to make any demands.
"He can't change back, no man really wants to go back to a boring human cock, no woman either. That's why men store the power and the magical sex merely propogates it, that is why my form has changed for now, but you will become a proud verile ever present member in our pack." having satisfied herself with the explanation Darleen gets on her hands and knees wainting for Cal to impel her.
Her words sound true to you, but you changed back didn't you? Looking down you see that your semi-erect cock is surrounded by a sheath covered in black hair. You gasp, and the air you breath in causes your erection to increase revealing the end of a shiny red and wet dog dick. The aroma of your mother in heat continues to arouse you, you need to fuck something, and fast, but what?...