He had her bent over the kitchen table, her big ass spread wide, and he wasn't holding back. "Fuck, Mom, your asshole is so tight," he growled, pushing the head of his cock against her puckered hole. She moaned loud, pushing back like she couldn't wait for it. "Give it to me, baby. Shove that dick up Mommy's ass."
They'd been dancing around this for weeks. Ever since she caught him jerking off to videos of older women getting their asses fucked, the tension had been thick. She was 42, thick in all the right places, with heavy tits and a round ass that jiggled when she walked. He was 19, built from the gym, and his cock was thick enough to stretch her open. One night she walked in wearing nothing but a towel, dropped it, and told him straight: "If you want to fuck my ass, do it right."
Now here they were. No more teasing. He spat on her hole, rubbed the head around it, and pressed hard. Her ring stretched slow and tight, gripping him as he sank in inch by inch. She gasped, fingers digging into the table. "That's it, stretch Mommy's asshole. Fuck it deep." He grabbed her hips and drove the rest of the way in until his balls slapped her pussy.
He started thrusting hard right away, no gentle bullshit. His cock plunged in and out of her ass, making wet, filthy sounds. She reached back and spread her cheeks wider for him. "Harder, son. Pound Mommy's shithole." He slammed into her, watching her ass ripple with every thrust. Her hole gripped his shaft like a fist, sucking him back in every time he pulled out.
She was dripping wet down her thighs.

He reached around and rubbed her clit while he fucked her ass. "You love this, don't you? Your own son wrecking your asshole." She nodded, voice shaking. "Yes, fuck yes. I've wanted your cock in my ass for months." He pulled out halfway, spat on his dick again, and rammed back in, making her cry out.
They moved to the couch. She got on all fours, ass up high. He knelt behind her and buried his face between her cheeks first, tongue fucking her stretched hole before he shoved his cock back inside. She pushed back, meeting every thrust. "Deeper. Fuck Mommy's ass like you own it." He did, gripping her waist and jackhammering into her. Her tits swung under her, nipples hard.
He flipped her onto her back, legs pushed up to her shoulders so her asshole was completely exposed. He slid back in easy this time, her hole already loose and sloppy from the pounding. He fucked her slow and deep for a minute, watching his cock disappear into her ass, then went back to fast, dirty strokes. She fingered her own pussy while he did it, coming hard around nothing, her ass clenching on his dick.
"Fill my ass, baby," she begged. "Shoot that load deep in Mommy's asshole." He couldn't hold it. He buried himself to the balls and unloaded, pumping thick ropes of cum straight into her guts. She felt every pulse, moaning as his hot seed flooded her. When he pulled out, his cum leaked out of her gaping hole and ran down to her pussy.
They didn't stop there. She sucked his cock clean, tasting her ass on him, then climbed on top and sat on his dick again, riding him reverse so he could watch her ass swallow him. She bounced hard, slapping her cheeks, demanding he spank her while she took every inch up her ass. By the end she was leaking cum from both holes, sore, satisfied, and already talking about the next time he'd fuck her ass raw.
They cleaned up eventually, but the secret was out. From then on, whenever the house was empty, she'd bend over or spread for him, and he'd take her ass like it was his. Raw, messy, exactly how they both wanted it.