"I don't know, daddy."

"I don't know, daddy..." Riley's voice hitches with a little tremble of trepidation. You reach up to stroke her cheek with one hand while continuing to core her sphincter with a finger.
"I need you to be strong, baby." You look into her eyes.
"I...I can be strong, daddy." She smiles weakly, taking shuddering breaths. "It feels weird..."
"By the time I'm done, it's going to feel good, but you have to relax." You work a little more earnestly with the finger, before pulling free to look through the nightstands and drawers. After about a minute or two, you give up, having not found anything that will do.
"We're going to have to make do, baby..." You climb onto the bed, letting your shorts and boxers stay on the floor. You pull Riley's hips up and toward you, spreading her ass cheeks. You spit directly onto her knot, and start to work your tongue. Her asshole is very clean, and tastes amazing.
"Ooooh.... daddy... that's....mmmmm...." Riley starts to moan. "That feels good...." You work two fingers into her snatch, pumping as you eat her ass. She starts humming and purring, and drumming her feet on the bed. After a minute or two, you straighten, pushing her hips downward to line up your hard dick with her snatch. You rub her entrance, then push in.
"Aahhhh!!! Oh...daddy.... you're so thick..." Riley squirms, pushing back to slide more of your cock inside her wet pussy, but you smack her ass cheek hard with your hand, and she gasps in pain.
"Stop that, Riley."
"...yes, sir." she stops trying to fuck back on you, and you press forward at your pace, a little deeper each time, until you finally fill every nook and cranny of her tight, quivering tunnel, stretching it and feeling it squeeze your cock on every surface. Good...god.... what a terrible and wonderful feeling. Your daughter's cunt is magnificent; even glorious.
"Nnnnnnnnnnnn!!!" Riley gives a low throaty moan as you fuck her deep, but gently, kneading her ass cheeks and giving the occasional slap to her already reddened flesh. As you fuck her, you work a finger back into her back door, until you're two knuckles deep and can feel your own cock through the walls of her asshole.
"Are you ready, baby girl?" You thrust harder.
"Y...Yes...Yes daddy....." she doesn't sound certain, but you pull free of her hungry hole anyway, pressing your cock head to her sphincter.

"aaaaaaaaaaaaaa........AAAAHHH......" Riley's voice raises an octave when you break through the resistance of her o-ring, plunging the head of your dick into her warm, tight tunnel. "OH FUCK!" The pain in her voice is undeniable, but she's still moaning.
"Good girl..." you slowly work deeper, as she whimpers and whines, tears leaking from her eyes.
"Daddy... you make me feel so dirty..."
"You wanted to get fucked by me, baby girl. You ARE dirty. But I'll fix that, don't worry..."
Over a few minutes, you slowly train her tight ass. She cries and whines, but she also moans and suckles on a finger when you stick it in her mouth, and eventually, you can thrust with relative ease. You spit on your shaft as it pumps in and out of her gripping butthole, and she works her snatch furiously with a free hand.
"Does...." she pauses to take in a sharp breath... "does it feel good, daddy?"
"It feels amazing baby." You can't deny how tight and warm her back tunnel is. She didn't lie; this hole was un-plundered.
"Bet....better than Mom?" she turns to look at you with one eye.
"Different, baby girl. Different." As nasty and wrong and hot as this is, that's the truth. Each girl has their own unique charms.
"Oh... ok..." her smile slips, and she looks a little disappointed. You respond by redoubling your efforts.
"AWWWHH!!! OH DADDY!! YOU'RE GOING TO BREAK ME-E-E-E!!!!"
"You don't compare yourself to mommy, you little slut, do you hear me?" you yell, punctuating words with savage thrusts.
"Y...Y...Y.. ES...ES...D...A...DD....Y....!"
"You're a dirty little girl who needs to be punished!" You smack her ass hard.
"Yes! I'm a bad girl, daddy!!!" Tears stream down her face, but her voice is pure lust. "Punish me!"
You can't contain yourself.
"Take daddy's cum, Riley. Take it in your naughty ass!!!" You pound until you shoot deep inside her asshole, filling it with spunk.
"Ahhhh.........." Riley slides off your cock with a pop, collapsing onto her side and shaking. She's holding her poor, abused asshole, feeling the cum as it trickles out.
"Good girl, Riley...you were so brave." You stroke her cheek, running fingers through her hair and speaking softly. "Daddy's so proud of you."
".....thank you, daddy..." her voice is small, and pained, but she looks at you with love. "It...it hurts, daddy."
"I know baby, I know. It takes some getting used to."
"It was good, too, though. It hurt, and felt incredible, too." She looks into your eyes. "I... I'd want to do it again."
"One time, baby. We said one time."
"I know... but...." she reaches out to touch your cheek. "I still need instruction, daddy."
"Oh, Riley." You scoop her up in your arms, giving her a kiss, and you rub her clit with a free hand. "Why do you have to cause me trouble?"
"I'm sorry, daddy..." she kisses your neck as you work her sensitive nub.
"It's okay, baby girl." You gently lay her on her back, taking up a position between her legs. "We'll figure it out."
You spend the next 6 minutes or so eating her pussy, giving her a nice reward for her work. She cums hard at the end, screaming your name and drumming her heels on the bed.

Another ten minutes to clean up, and you each leave separately to head to your cars, careful not to be seen together. "I'll see you at home, daddy. I've got to go pick up Alli."
"Okay, Riley."
You climb into the Javelin, and head home, rolling into your driveway around 2:15.