US sans x UF grillby (COMPLETED!)

chapter 17 you owe me a dare

"can you do something for me?"
Grillby looks at him confused.
"What?"
"I want you to do a dare for me. You owe me after all.dont you?" He says softly.
"What would that be?" He asks grinning at him.
"I dare you.... to...."
He gets closer and whispers in his ear.
"Fuck me..."
He raps his arms around sans waist again pulling him into a hug.
"I thought you'd never ask. But it's gonna be a challenge. Hehe."
They nuzzle each other's nose then kissing. Sans summons his tongue making it glow bright blue. Grillby pulls out his bright pinkish purple tongue and ask for entry. Sans allows him and he doesn't the same for grillby. They hold each other tightly making there kiss deeper and more wet as they go. He grabs sans and pulls him back making sans fall onto of him. They break the kiss. "Did you want e to lead?" He says in a seductive voice. Grillby nods I'm silence. He sits onto of the fire monster leaning over and once again livking his neck. Warning moans and gasps of please while he also strokes down his body and into his pants.
"You like that?" He smiles while grillby moans loader. He brings his hand back out and puts it around grillbys cheek. "...."
"Yknow sans I thought you were here one dating me to fuck you?"
"Your the one who pulled me over you." He chuckles.
"This was only to test you."
He looks at him confused.
"Test me on wha-" he moans as he feels his talebone grabbed and stroked backa nd forth. "You dick."
"Hehe"
He slides his shorts down then grabbing his back bones and liking up his spine causing him to moan. He covers his mouth in an attempt to keep quiet.
"I thought you were supposed to be on guard you are a royal guard after all. for all he could know it may be a blizzard it can still travel.
Grillby pulls his member from his pants placing it inwards without sans notice. I'm a surprise attack as sans was distracted by the moans, grillby slides him back at full force thrusting it straight into him. He raps his arms around sans back pulling him into a hug. Sans feels paralyzed from the sudden shock unable to move in his arms. He tried to fight but all he feels is pain and pleasure all at once. It feels so good. He moans while grillby forces him down pushing it deeper into him. "I know that was hard for you but, This is what you asked for isn't it?" Sans tries his best to speak.
"Please be gentle."
"I will." He places a kiss on sans head. He starts to thrust in and out slowly u til he was used to the size of his member. He went faster and faster until sans was at his limited and apparently so was grillby.
"I think I'm going to-" cum filled sans spilling out of him and onto the bed. The gasp for a moment before grillby pulled himself put of sans and letting him fall over to the other side of the bed.
They calmed down for a few minutes before cuddling each other in bed before falling asleep in each other's arms for the rest of the night.
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Hey guys hope you enjoyed this I'm a undertail trash and fontcest but I love it. Haha! Thanks for reading there are more chapters on the way!