Give her the business.

"Don't worry..." you stick your thumb in your mouth, wetting it, before spreading her cheeks and circling her butthole with the digit as you pound her into her shaking orgasm.
"Oooo....what are...."
You push inside, and Lucy coos. "Oh, baby... how did...you...know?" She looks back, eyes glazed and face sweaty.
"I didn't know...I just do what I want." You fuck her with long, deep strokes as your probe her backdoor.
"Well....I happen...fuuuuuuck....I happen to like that shit...." she falls onto her arms. "Smack my ass, baby." You oblige, giving her luscious cheek a firm strike with your other hand, squeezing after you make contact. "Ah! Mmmmm...." she moans. You slip your thumb in up to the second knuckle, feeling your own dick through the walls as it fills her pussy, and slackens, fills, then slackens.
"You can get....more in there....I believe...in youuuuufuck...." Lucy's panting, talking nasty shit. You pull your thumb free, and replace it with the middle and ring finger, spreading her little knot wide.
"Ahhh!!" She shrieks. "Mmmf....Mmmf!"
"You asked for it, you dirty slut." You smack her ass very hard this time, and she yelps in pain. "Don't cry over it now."
"I love it...I'm a dirty slut... spread me more, baby." She's fucking back hard. She really is a dirty slut.
"Okay....I've got something that will split you open." You hold her asshole open with your thumbs, pulling out of her snatch and pressing your dick against it.
"Oh...fuuuuuck.....I don't know if I'm.......Aahhhhhhhhhhhhhhhhhhhhhhhhhhh!!!!!!!!!!" She wails as your press in. "Oh baby...oh baby.....thats so thick...."
"Take it." You start pumping into her tight asshole. It's elastic enough that you can pump easily with only a little prep, but still tight enough to hug your thick cock on every side. "Jesus Christ.... you have an asshole to kill for, Lucy."
"Ah! Ah! Ahh! Mmm... Mmm.... Mmmm....." she's gone, beyond words now. She whining and panting and her face is pinched with pain and pleasure. "Am I...stretchhhhing you enough, baby?" You hilt yourself, and her eyes pop wide open.
"Unnnngh......." she starts to frantically rub her clit, and squirts violently onto the bed sheet, splattering your legs. "You made me....god...."
"What a coincidence..." you pump furiously, and shoot a load into her hungry ass.
"Oh.....fuckkk....." her knees buckle, and you bear her down flat onto the bed, squelching in the puddle of her squirt. You pull from her knot, and a stream of white follows, mingling with the liquid as Lucy pants and whimpers.
"Wow... I knew you were a good time girl... but I didn't realize you were a such a freak, Luce." You clean yourself up with her shirt, and pull your boxers on.
"Mmm.....mmmm...." she's still recovering. Her head lolls as she rolls onto her side. "Th...anks..." her crotch is plastered with cum and squirt, and the bed sheet has a huge wet spot.
"Sorry for the mess, heh..." you chuckle.
"It's no big deal. It's not like it's my house." she smiles, but then she falls back. "Fuck. That was intense..."
"I've got to split. Maybe another time?" You pull open the door.
"Oh, for sure..." she's still dazed.
You grab your shorts, get dressed, and head out. Jack's nowhere to be seen, but you can hear two sets of snoring from the other bedroom. You return the cart, get into the Javelin and head home. It's about 2:40 PM when you roll into the driveway.