The sanding finally stopped at 4 p.m. The crew packed up and left, but the whole house still vibrated with leftover danger.
I barely caught my breath from the desk quickie before Mia dragged me upstairs by the wrist, fresh cum still leaking down her thighs. She kicked the door shut, spun me around, and shoved me onto the bottom bunk like she owned the room.
"Time for the rules," she announced, eyes sparkling with pure evil-brat glee. She grabbed her phone, opened the stopwatch, and waved it in my face. "Two games from now on, little bro. Fastest time to make you explode… versus how long I can edge you before you're begging. Loser wears the winner's cum-soaked panties under their clothes all day tomorrow."
I opened my mouth to argue. She dropped to her knees, yanked my shorts down, and swallowed my cock in one aggressive plunge—still half-hard from the lecture.
"Round one," she mumbled around my shaft, already bobbing like a machine. "Fastest cum. Go."
The stopwatch started ticking.
Mia went full pornstar—no mercy. Wet, sloppy, aggressive sucking—hollowed cheeks, tongue attacking the underside, one hand jerking the base while the other rolled my balls. Her free fingers rubbed her own cum-filled pussy like the sound of me getting drained turned her on more than anything.
"Fuck—Mia—" I groaned, gripping the sheets.
She popped off just long enough to smirk. "Twenty-three seconds already. Beat your record, loser."
Then she deepthroated me to the root and hummed. My hips bucked. Thick ropes shot straight down her throat as the timer hit 47 seconds. She swallowed every drop, pulled off with a wet gasp, and held up the phone like a trophy.
"New record: forty-seven seconds," she gloated. "Your stepsister's mouth is officially better than your hand ever was."
She didn't let me soften. Climbed up, straddled me reverse-cowgirl on the bottom bunk, and sank down onto my spent cock. The sloppy creampie from earlier made the slide effortless.
"Round two," she purred, starting slow, grinding rolls. "Edging. I'm keeping you right on the brink until you cry for it. Timer starts… now."
She rode like she had forever—deep circles dragging her clit along my base, then lifting until only the head stretched her before slamming back down. Every time my balls tightened she slowed to a torturous crawl, squeezing her pussy like a vice.
"Feel that?" she whispered, eyes on the stopwatch. "Five minutes and you're already throbbing like you're dying. Imagine how massive the load's gonna be when I finally let you explode."
She grabbed her phone again, switched to video, and angled it down between her legs. The screen showed everything: my thick cock disappearing into her creamy pussy, earlier loads frothing white around the base, her swollen clit shiny and desperate.
"Say it for the camera," she ordered, still riding slow. "Tell the video who's better—me or Mom's crusty panties."
"You," I gasped, hips twitching. "Fuck—you're better."
"Louder." She sped up just enough to torture me. "Tell it you're done jerking into Mommy's thongs. From now on every load goes straight into your stepsister."
I repeated it like a broken prayer while she recorded—ten seconds of pure filth, my cock pulsing inside her, pussy lips stretched tight, cum already leaking out. She stopped the video, tossed the phone aside, and grinned.
"Proof. Now… beg."
Eight minutes. Nine. I was losing my mind. "Please—Mia—I need to cum—please—"
She slammed down hard, riding like a demon, tits bouncing under her tank top. "Beg louder. Tell me you'll let me ride you every single night for the next four months."
"I will—fuck—every night—please—"
She slammed down one final time and squeezed.
I erupted—the biggest load yet—thick, heavy, endless ropes pumping so deep I felt it splash against her cervix. Mia came with me, thighs shaking, biting her lip bloody while her pussy milked every drop.
When she slid off, a river of fresh white cum poured out onto the sheets. She scooped some up, smeared it on her fingers, then hit record again for a quick 10-second clip: spreading her pussy lips so the camera could watch my load drip out in thick, obscene globs.
"Proof I'm better than any of Mom's panties," she whispered to the lens, then stopped it. "And tomorrow? Both games back-to-back. Winner picks where we fuck next—maybe right in Sophia's bed while she's in the shower."
She climbed up to the top bunk for once, still leaking, and blew me a kiss.
"Sweet dreams, loser. You owe me panties tomorrow."
I lay there on the soaked bottom bunk, cock twitching, heart racing.
Mia wasn't just fucking me anymore.
She was turning us into a filthy competition.
And Sophia still had no idea her panties were about to become the grand prize.
End of ch 7.