She lived alone on the edge of town with nothing but her massive Great Dane, Titan, for company. At twenty-eight she had tried men and found them boring, quick, and selfish. Titan was different.

He was huge, all muscle and fur, with a heavy sheath that swung between his hind legs whenever he got excited. She had noticed it months ago and the thought had lodged in her head like a splinter she could not pull out.
One humid afternoon she stripped naked in the living room, the blinds drawn. Titan padded over, nose already twitching at her scent. She dropped to her knees on the rug and reached under him, wrapping her fingers around the warm, fur-covered sheath. His cock slid out fast, thick and red, the tip already dripping. She stroked him slowly at first, then harder, watching the knot swell at the base. “Good boy,” she whispered, voice thick. “Show me what you’ve got.”
Titan’s hips jerked forward. She leaned down and took the pointed head into her mouth, tasting the sharp, musky pre-cum that leaked steadily. It was hotter than any man’s. She sucked greedily, one hand pumping the shaft while the other reached back to spread her own wet pussy. Her fingers slid inside easily; she was soaked just from the idea of what she was doing.
She pulled off his cock with a wet pop and turned around, presenting herself on all fours. Titan mounted without hesitation, front paws landing on her back, claws scraping lightly. His cock jabbed between her thighs until she reached back and guided it. The first thrust missed, sliding along her ass. The second hit home and drove deep in one long, powerful stroke.
She cried out, the stretch sudden and perfect. Titan fucked like an animal, fast and relentless, his hips slapping against her ass. Each thrust pushed the swelling knot closer to her entrance. She pushed back, greedy for it, feeling the thick bulb stretch her wider with every slam. When it finally popped inside she screamed, the pressure intense, locking them together. Titan kept thrusting in short, brutal strokes, the knot grinding against her G-spot.
Her orgasm hit hard, pussy clenching around the dog’s cock, juices running down her thighs. Titan growled low and came, flooding her with hot, thin spurts that kept coming in waves. She stayed on her knees, shaking, the knot keeping every drop inside her. They remained tied for nearly twenty minutes, her breathing ragged, his heavy body draped over her back. When the knot finally shrank enough to slip free, a thick rush of cum poured out of her stretched hole and puddled on the rug.
She did it again that night, and the next day, and every day after. Sometimes she lay on her back with legs spread so Titan could lap at her cunt with his long, rough tongue until she came against his muzzle. Other times she bent over the couch and let him mount her from behind, the knot swelling inside her while she rubbed her clit and begged him to fill her. The dirty, secret thrill never faded; the sheer size of him, the animal urgency, the way his cum leaked out of her for hours afterward.
She never told anyone. It was hers and Titan’s, raw and filthy and exactly what she needed. Every time he mounted her she felt owned, used, and completely satisfied in a way no human had ever managed.