"I swallowed 20 loads."

Sweetie smiles with pride.

"Grandpa only told you to swallow 10." Grandpa says, trying to stay stern and suppress a smile.

"I want to be a bigger slut than Grandpa thinks I am. Even if it means disobeying." This comment is met with another slap hard across her face, just as she knew it would be. And she feels the orgasm start to build in her body.

"Grandpa wants you to prove it." He says.

And she knows what that mean. She hurls her throat onto Grandpa's member and begins to thrust her face against it. She remembers when they started this, how Grandpa would have to hold her in place as he skull fucked her. How the sensation of his cock going past her tonsils and into her throat was so chocking. Now Grandpa can practically stay still and she'll do all the work.

She knows exactly what comes next. Her body tenses up, her makeup runs down her cheek, her sweat covered flesh is covered in even more sweat. She begins to wretch. She doesn't have to make a "gah, gah, gah, gah" noise as the cock hits the back of her throat, but she knows Grandpa likes it. Her vision starts to cloud over. She feels the jizz in her belly start to rumble and want to return. And she wants it to. And it does, pouring from her lips and nose. Pouring all over Grandpa's cock and onto the hardwood floor.

Grandpa's always asking her to swallow load and then prove it to him. And it's never hard to find them. 10 guys in a day. 20. One time 50. Their town has biker bars, bowling alleys, and a university and that university has fraternities and sports teams. Easy.

Grandpa pulls his cock from her throat, and she falls to all fours, panting, spit dripping out of every inch of her young mouth.

"This isn't 20 loads of jizz." She hears Grandpa say, and she opens her eyes as her vision clears up to look at the mess down beneath her.

"No Grandpa, it's not." She takes a deep breath. Thank goodness it's not all there. Now she gets to do it again.

And she does, gagging on her Grandpa's hot cock, one hand making a fist, punching the back of her own head so it pushes down as far as possible, the other hand, down between her legs, rubbing her clit furiously. She knows she can only climax when she's gagging. This is one of the things Grandpa has taught her. He's taught her so many things.

Again, more cum pours from her mouth, as lightning sparks from her clit into her entire body. Grandpa pulls his cock out of her throat for a moment, but she needs a few more seconds to cum, so she slides her fingers to replace it and as she feels her rapture peak, she also feels Grandpa's hand come across her face again. What a moment.

She falls to the floor, lying there, panting, exhausted, ecstatic. Grandpa's cum hits her face. A final moment of joy. She loves what she's become.

"Now." Grandpa says. "Shall we get your mother to clean this mess up?"