Naughty, your sister-in-law’s dog, had been following you around all afternoon at the cookout. He’d stick his head under your skirt every chance he got. Everyone was laughing about it. Making jokes. You’d just push him away and try to be good natured about it. You got up to go into the house to use the bathroom. You made your way to the one in the master suite since the other was taken. The dog followed you. While you were peeing he turned the door handle and entered the bathroom.

Your short skirt was around your waist and your panties were around your knees. You eyed the big dog nervously. Then you saw it and gasped. The chiseled pink tip of his cock was peeking out. He growled demandingly. Your pussy spasmed. You knew what he wanted.

“Good boy Naughty. Go away,” You tell him, but he just stood there staring through you and asserting his dominance.

You reached down to pull your panties up. The attempt to deny him only elicited a loud menacing growl from the beast. Your knees slammed together, which caused your panties to fall to the floor. The big dog swooped in and took hold of your thong. Shaking his head violently he pulls them off you. You felt another spasm in your cunt from his dominant display. You couldn’t help yourself. You felt yourself getting wet.

He forced your knees apart with his toothy muzzle. You whimpered. Turning your head, you closed your eyes. Then you felt it. His rough and long tongue working your folds. You hadn’t wiped yourself yet, but he took care of those stray drops of piss. Your hands fell to his broad head. You intended to try to push him away, but his tongue felt so good on your pussy that you found yourself pulling him closer. You leaned back against the tank and spread your thighs, giving him full access to your smoothly shaven pussy.

You don’t see her, but your younger brother’s wife was standing outside the door looking through the narrow slit where the door hinges to the frame. Her right hand was in her unbuttoned shorts. You didn’t hear her close her bedroom door or cross the carpeted bedroom floor.

Naughty licked you eagerly. You feel the familiar sensations of an orgasm approaching, the butterflies behind your belly-button and the building tensions in your pelvis. You hate herself for enjoying the dog’s tongue, but it had been so long since you’ve gotten fucked properly that you can’t help it.

The way he licked you edges you. You’re frustratingly unable to cum. He backed away while staring at you expectedly. Realizing you were about to orgasm on a dog’s tongue you come to your senses.

“What the fuck am I doing?” you asked yourself.

You sit upright and closed your knees with the thought that what just happened is going to haunt you for years to come. You stood, pulled down your skirt, and stepped towards your thong lying under the window, hoping they were still wearable because your skirt was so short.

Suddenly, Naughty hit your knees from behind and you went down, but you caught yourself before your face smacked the floor. Your short skirt rode up your hips.

“Naughty! You asshole! Fucking dog!” you exclaim in exasperation at the unruly animal.

You had no more than gotten the words out than Naughty is on your back. The big dog slipped his front legs around your waist. You realized in horror that he’s bigger and stronger than you and that he wanted to make you his bitch by fucking you. The thought excited you momentarily.

You tried to drop your hips, but his grip around your waist was too strong. You pushed yourself up high on your hands, but he responded by growling loudly in your right ear. You would have pissed yourself if you had not just emptied your bladder.

“Good boy Naughty. Just don’t hurt me,” you pleaded.

You eased back down. Naughty began thrusting. You felt the hot wetness of his pre-cum land on your thighs and ass-cheeks. In desperation you wiggled your ass from side to side in attempts to evade his lust to breed you. That only angered the dog. Naughty knew how to handle uncooperative bitches.

The massive dog growled the loudest yet. He then lightly bit around the back of your neck without breaking the skin. You froze. His rear paws shuffled closer to you while continuing to thrust blindly until he found your entrance. You moan as he thrust inside you. The smooth dog cock pushed deep inside you and against the walls of your cunt. He had you then. He fucked you hard and fast, the way you wish men could. The heat of his prick was a novel sensation, but you liked it. His expanding knot forced its way through your labia. The pain and pleasure cocktail was delicious. You were becoming fuck-drunk. You always enjoyed your fucking on the intense side and Naughty’s fucking was intense on a level you had never imagined.

The orgasm that had evaded you earlier built again. You lost yourself in Naughty’s fucking and in the way he totally dominated you. His swelling knot stretched your entrance further than you’ve even been spread. You groan and suddenly his knot entered for the last time with a pop. His cock tip pushed against your cervix and his knot rubbed against your g-spot. Naughty began to unleash his nut in you. The heat is exquisitely taboo and wicked. You cum harder than you ever had before. You shrieked as you squirted your cum across the bathroom floor towards the door.

You came down from your orgasmic high and rested your head on your forearms.

“Naughty, why can’t I find a man who can fuck like you?”

Knowing you were knotted and under Naughty’s control, your sister-in-law stepped into the bathroom, carefully avoiding your squirt.

“Because of biology. Men and dogs just aren’t built the same,” she answered.

You jumped at the unexpected voice and said, “He raped me. I didn’t want this, but he forced me. I was afraid he attack me.”

“Hush, you can’t lie to me. I saw you squirt around my dog’s cock and knot. Orgasms don’t lie. You wanted it. Your brother told me all about your preference for bad boys.” She patted her dog on his back and said, “Naughty here is the baddest boy around. I knew when you told me you were on your period a couple weeks ago that you’d probably be ovulating during the cookout. Naughty finds the scent of women in heat irresistible. Don’t you my naughty boy? Yes you do. Yes you do.”

Just then Naughty released his grip around your waist and threw his right foreleg over your back. Moments later his right hind-leg was thrown over your ass, giving you a scratch in the process. His knot rotated in your sweet pussy, which caused you to moan in pleasure as he continued to spurt his puppy cream into you.

“Oh my, what a lovely turned tie,” your sister-in-law said praising her good boy.

Your sister-in-law sat and watched as her dog continued to get his nut. After about ten minutes, Naughy’s balls were almost empty. They had been drained by his mistress only that morning. He started pulling against you, his new bitch.

“Grab his back legs! His knot is probably still too big,” you obey by taking hold of his hind-legs to hold him in you longer. “I had a hunch that you and Naughty would hook up sooner or later.”

“I think he’s small enough to come out now,” you say. You let go of his hind-legs and Naughty pulled away. His knots popped out, followed by his cock and a gush of opaque watery dog-cum. Naughty started licking his cock clean and slowly made his way towards his bed.

You were shaken by your first experience of dog-sex and at having been caught by your sister-in-law. Your sister-in-law handed you a wad of toilet paper and wet washcloth. She then cleaned the floor with a wet washcloth and towel. In silence you cleaned yourself up the best you could. She offered you an absorbent pad. You slid on your slobbery panties and slipped the pad in place.

“Please don’t tell anyone. I’d die if anyone found out,” you beg.

“I promise I won’t tell anyone… except for Runt,” she averred using the family nickname for your brother given to him because of a late growth spurt. “It will be our little secret.”

“Please don’t tell him,” you cry in desperation.

“Honey, I have to. He and I don’t have secrets from each other. Even though I’m the boss around here, we swore to each other that there wouldn’t be any secrets between us.”

Seeing that it was pointless to convince her otherwise you fell silent again. Suddenly, your brother’s marriage to a girl from a wealthy family made sense. Your sister-in-law was cucking your timid brother with Naughty. The epiphany shown through your eyes. Your sister-in-law takes your hand.

“Come, let’s go find my husband and tell him Naughty has a new bitch.”

You follow numbly, knowing that both she and Naughty have their hooks in you. As the two of you search for your brother, you smile at the thought of serving as Naughty’s bitch again.