“Don’t worry, Mrs. Smith! Your house and your lovable dog will be safe with me this weekend!” Penelope gave Mr. and Mrs. Smith a quick salute, smiling brightly as the married couple prepared to leave. They were going on a weekend vacation and had called her to watch over their dog. The house was important, of course, but someone had to be there to feed Buster and take him outside. They had a good working relationship with Penelope, who was their next door neighbor. She had been taking care of Buster while they were away for months, and they trusted her above a kennel or another sitter.

“Thank you so much, Penny. We really appreciate you watching over him for us. Alright now, be a good boy, Buster.” Mrs. Smith leaned over and patted their good-natured great dane on the head, which he happily pushed against. Then she stood back up straight, the couple waving to Penelope as they dragged their suitcases past the front door. “Bye you two! Remember to call us if you’re having any trouble!”

“Not to worry! Bye bye!” She waved after them, then closed the door and locked it. “Alright, time to get my grub on!” She hurried towards the kitchen, Buster ambling along behind her. She was used to having him follow her, though. As a dog person, she enjoyed spending time with them, and it seemed that Buster had been fond of her since they first met. He’d always been such a good boy that she never had to worry about him destroying the house while her back was turned. He was always so excited to see her too.

There had been a nice and moist piece of cheesecake left in the fridge just for her, so she gladly took it and brought it back to the couch along with a fork. She chowed down while watching TV, with Buster resting comfortably next to her feet. Occasionally she would pet him with her right foot, which he seemed to enjoy. His tail would wag whenever she did so, then he would settle back down when she was finished. Leaning back against the couch, she continued to watch TV until she had finished her slice of cake and the show she was watching had come to its conclusion.

“Alright, I think it’s time for a bath.” She got up, stretched and went to the kitchen to wash off her dishes. Then it was off to the bathroom, which had a large, luxurious bathtub. “I’ll never get tired of this,” she sighed happily to herself. The Smiths were pretty well off, and they had put a lot of their money into their house. That made watching over it not much of a chore. She could fill the tub full of water, put in some scented bubbles, then sink down into the water and relax as long as she wanted.

Her back was turned to the door, which she hadn’t bothered closing. After all, it was only her in the house, so she had all the privacy she could ever want. She then began to strip off her clothing, starting with her school-branded t-shirt and red bra. Her large, heavy breasts were perfectly perky, her charm point if one was to think in such a manner. She then pulled down her skirt and matching red panties, her ass none too shabby in size either. Her clothes went into a small pile near the sink, and then she approached the bathtub.

“Oh, the stopper isn’t plugged in.” There’d be no point in starting the water if it was all going to go down the drain immediately. She dropped down to her knees, then bent over the rim of the bathtub and reached for the stopper. Little did she know that leaving the door open had allowed Buster to follow her inside, standing there at the doorway and staring at her naked beauty. She had no idea how she made the non-neutered dog feel, and now she was practically showing off her nudity to him. It was as if she was begging him to do something. That was how, in one instance she was just bending over the tub, and in the next Buster was mounting her.

“H-Hey! Buster! What are you doing?!” She looked over her shoulder, seeing the great dane lying atop her back. It looked like there was excitement in his canine eyes, his tongue hanging out, and even then Penelope didn’t understand the full scope of what was happening. Then she felt something hard growing across her plump ass, and that was when all the pieces fell into place. “Buster?!” Her knowledge of sex was pretty limited to what she’d learned in health class. She’d masturbated a few times, but she’d never even kissed another person, much less had sex with them. Did Buster want to have sex with her? That couldn’t be. She was a human! There was no way!

How was she supposed to explain what was happening, though? That was definitely his cock pressing against her ass, now fully unsheathed. “B-Buster, wait a minute!” She tried to push him off, but his weight made him too strong for her to buck. She was stuck where she was, buck naked and bent over the bathtub. His hips began to move as he rutted awkwardly, trying to get his cock inside her. “Buster, no! Bad boy!” No matter what she said, though, it was all useless. He was too horny to be stopped.

She felt his cock prodding at her thighs, trying to reach its mark. Finally, after a few false starts, she felt his cock break past her lower lips, sinking into her tight, now-deflowered pussy. “Ahh!” It was painful: more painful than she’d expected. Then again, how was she to expect something like this to happen? She’d had her virginity taken by a great dane! Buster was thrusting now, barking happily above her and wagging his tail furiously. His paws were on her shoulders, further keeping her pinned to the spot.

The more he thrusted, the more it became… enjoyable? She didn’t want to attribute such adjectives to what was happening, but she couldn’t deny that she was starting to feel good. As the pain from being deflowered passed, pleasure soon took its place, and soon her eyes rolled back and her toes curled. Without warning, she came, and she came hard, tightening up around his cock. Even through the haze of post-orgasmic bliss, she was panicking. ‘Did a great dane just make me cum?!’

Whether Buster understood what had happened or not, he kept on thrusting regardless, though his thrusts did seem to have more power to them. It was as if he was trying to drive her to another orgasm. She shut her eyes tightly and moaned loud, her breasts swinging back and forth as her body was slammed into again and again. He was a relentless lover, his lower half clapping against her jiggling ass and his tail wagging with his thrusts. Then it was moving up and down instead of back and forth, whapping against her ass like he was spanking her. She’d never been spanked before, not even as a child. Why did she like it so much?

Suddenly she felt his jaws clamp down on her neck. She felt his teeth digging into her skin, drawing drips of blood to the surface. It wasn’t extremely painful though, and something inside her knew that he wasn’t trying to harm her. While in the middle of coitus, she had her mind draw back on any information she knew about dogs, and came to a quick conclusion. He was marking her as his own: he was claiming her. Something about that thought held appeal to her, at least in the moment. It was enough to make her cum again.

She soon lost herself to the pleasure, time becoming a nonfactor. He kept thrusting and she kept taking it, fingers gripping and slipping on the smooth surface of the bathtub. As shameful as it was, Buster was making her cum again and again, to the point where she eventually lost count. It was all a blur, and she was starting to feel numb. That was when she felt something new pressing against her pussy lips. As wasted on sexual pleasure as she was, she didn’t know what it was at first. By the time she realized that it was Buster’s knot, he was thrusting hard enough for it to pop inside her.

A cry of agony died on her lips as she felt his cum flood her insides. She felt so incredibly full, like she’d gorged herself on the finest meal. It caused her to cum one last time, and then she slumped uselessly against the tub, down for the count. Buster pulled away from her neck, gently lapping up the blood and soothing the puncture marks he had left behind. Then he flopped down on top of her, completely satisfied. They weren’t going anywhere for a while, she she had to come to terms with being beholden to his knot’s schedule. Now she really needed a bath.

Eventually he was able to pop his knot out of her pussy, and she was finally able to draw her bath. She soaked in the tub for quite a while, with Buster staying by her side the entire time. Once she was finished, she dried herself off, then blow-dried her long auburn hair. After that routine was complete, she grabbed a fluffy white robe and tied the sash around her waist. Her body was feeling the satisfaction of a long bath after a long lovemaking session, and she needed to hit the hay. However, as soon as she climbed into bed, Buster jumped into bed after her.

“Buster, you know you’re not allowed in bed.” He just stared at her, wagging his tail back and forth. “… Okay, but just this once, alright?” He barked happily, moving until his body was pressed up against hers. She smiled and kissed him on the mouth before closing her eyes. “Goodnight Buster. If you’re good…” She opened one eye, looking at him seriously. “… then maybe I’ll let you bend me over the couch next time.” Buster was such a good boy that he didn’t make a peep the rest of the night.