Grandpa wants to make more of a mess of her

"With your clothes off you don't really look that dirty," he said, "so I think we should get you more dirty so that you really need that shower."

"Oh is that so?" Carrie said, her head tilting to the side a bit as she smirked at your grandfather. He didn't meet her gaze, his eyes still focused on her tits as he openly gawked for several seconds before responding.

"Yes, and you're gonna give me what I want, right?"

There were a few seconds of hesitation from Carrie. At this point was she even doing this for your sake anymore? She had no idea you were watching, was this all to keep with her little 'Anything' promise to you earlier, or was she genuinely enjoying this little game of teasing and flirting with your grandpa?

"Well that depends. I did promise to make you feel better since you miss your wife, so I don't mind doing some stuff for you to cheer you up," she said, pausing for a split second before adding "within reason of course."

"You're such an amazing girl," he said, and you saw his hand caress her cheek before it slowly moved to her bare shoulder. "Now drop to your knees for me."

There was another slight pause as Carrie hesitated once again, but soon you were watching your girlfriend ease herself down onto the plush bathroom rug. She took a few seconds to shift around, kneeling in front of your grandfather with her big eyes gawking up at him.

"Now I've gotta get naked too so I can join ya in the shower, so take out my cock," he commanded. Once more there was a slight bit of hesitation in your girlfriend, but it faded as Carrie's hands soon traced up his legs. Her fingers seemed to be shaking a little as she worked to undo the button at the front of his pants, and your grandfather speaking up again made her jump a tiny bit.

"Slowly. Savor the build up before you're gagging with my dick in your mouth," your grandfather said. Carrie's hands were resting over his cock as she suddenly stopped trying to undo his pants.

"Well I know that's not gonna happen," Carrie said, clearly trying to maintain her control over the situation and set up some sort of boundaries. Your grandfather looked disappointed, but his familiar smirk quickly returned as he was looking down at her.

"You sure about that sweetheart?" he said, "do ya think I'm bigger than my grandson?"

The question lingered in your own head as soon as he asked it. It was difficult to tell but your grandfather seemed to have a decent size tent in his pants. Could he really be bigger than you? You quickly shook the thought away, you were secure in your own size after all and most guys were around the same average length and width anyway. Huge dicks were only really in porn, right?

"Not that it matters in getting me to suck it, but I really doubt it," Carrie said, giving a tiny laugh after. Her gaze flittered back down to the bulge in front of her for a fraction of a second before returning to his eyes.

"How about a dirty little bet then?" your grandfather offered. Carrie leaned back and looked up at him before he continued with his idea.

"Because I think I'm gonna put him to shame and show you a real man's cock, and I think you're gonna love it. So for every inch I'm longer than him you have to obey one command from me. That means you do absolutely ANYTHING I say, no matter what. No 'within reason' bullshit, no limits. Deal? Or are you worried your tiny dicked boyfriend won't be able to measure up to an old man?"

Despite the fact that she had nothing to gain here, Carrie was intensely competitive and wasn't about to let your grandfather belittle you like that. She gave a shrug and an almost arrogant smile came across her face.

"Why not, you're on. Just don't expect me to feel bad after you come up short and can't compete with your grandson," she said. She shifted forward and her hands moved once more to the front of his pants as you looked on, with higher stakes now on the line in this little back and forth game between your own grandfather and your girlfriend.

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