"You want… to play?" Makoto purred, a low, dangerous rumble in his chest. "Fine."
He leaned down, his movements slow and deliberate, a performance for their captive audience of two horrified senior citizens.
He began to pick up the spilled popcorn, his fingers brushing against her thighs, a tantalizing, feather-light touch.
Then, his face dipped lower, disappearing between her legs, into the warm, dark space under her skirt. He started by sucking and licking her inner thighs, the skin soft and warm against his lips.
"A bit… salty and sweet," he murmured, his voice muffled by her skirt.
Yuna's entire body seized up, her hands flying to his hair. Not to pull him away, but to shove his face deeper as her thighs clamped around his ears like a vise. The elderly couple gasped again, their faces a mask of pure, unadulterated horror.
Without breaking eye contact with the movie screen, Yuna flipped them off.
"Keep going," she gritted out, her voice a strangled, desperate whisper, as an action hero on screen was brutally decapitated in glorious, bloody surround sound.
Her hips jerked minutely against his mouth, a tiny, involuntary movement. "And if you stop before I..."
The seat behind them kicked violently as the man seated there cleared his throat in a loud, pointed gesture of disapproval.
Yuna's hand shot out, snatching a handful of popcorn from her lap and hurling it directly into his face.
"Mind your own damn business, grandpa!" she hissed, her voice a low, venomous snarl.
Makoto, emboldened by her sheer, audacious defiance, pushed further.
He pulled aside the thin, lacy fabric of her panties with his teeth, his tongue finding her slick, swollen labia, then her clit.
She tasted of salt and her own unique, musky sweetness. "Nice…" he murmured against her, "so tasty, little sis."
Yuna's back arched off the seat with a soundless scream, her fingers yanking at his hair hard enough to tear.
Onscreen, Tanjiro used Sun Breathing, releasing a fiery firewall. The deafening sound drowned out the wet, obscene noises coming from between her thighs.
"F-fucking!!" Her whisper was pure venom, laced with a desperate, all-consuming pleasure as she ground against his mouth.
The man behind them, now covered in popcorn and righteous indignation, stood up in protest. Yuna gave him a middle finger, while her other hand shoved Makoto's face deeper, a silent, frantic command.
When her climax hit, she slammed her fist against the armrest and bit her lips to muffle her moan, her knuckles white, her entire body trembling with the force of it.
As the credits began to roll, a cheerful, upbeat song filling the now-brightly-lit theater, she collapsed bonelessly into the seat, her legs still spread wide around him, a beautiful, ruined mess.
"Well, well," Makoto chuckled, his voice a little hoarse as he slowly resurfaced from under her skirt.
He gently fixed her clothes, his fingers brushing against her still-quivering thighs.
He stood up, helping her to her feet, his arm a steadying presence as she wobbled. "I hope we don't get banned from this theater."
He looked at her, a playful, innocent grin on his face. "Was that a good movie? I think I missed the last battle."
Yuna stumbled on unsteady legs, her face a furious shade of crimson as she shot a murderous glare at the horrified theater staff, who were all staring at them with their mouths agape.
"Worst. Movie. Ever," she hissed through gritted teeth, but her thighs were still trembling against his, a betraying, undeniable testament to her pleasure.
The moment they were outside, in the relative anonymity of the crowded street, she shoved him against the wall, her small frame vibrating with a potent mixture of fury and residual arousal.
"You," she growled, her voice a low, dangerous thing, "are buying me SO many Genesis Crystals to make up for this."
Her teeth sank into his shoulder, a sharp, possessive bite that was hard enough to leave a mark through his shirt.
"…And you're carrying me home," she demanded, her voice a little softer now. "My legs feel like jelly, you fucking animal."
Despite her glare, she nuzzled her face into his neck, a rare, fleeting moment of vulnerability before the mask of the bratty, manipulative stepsister slammed back into place.
"Fine, fine," he sighed, a genuine, fond smile on his face. He crouched down, letting her climb onto his back.
Her arms wrapped around his neck, her legs around his waist, her body a warm, familiar weight.
"This feels… nostalgic," he murmured, a genuine note of affection in his voice. "It reminds me of last month, when we fucked for four hours with you in your Klee costume."
Yuna's grip around his neck tightened to a chokehold-like level. "I will THROW US BOTH INTO TRAFFIC," she snarls, but her thighs squeezed his hips anyway, a silent, physical contradiction to her words.
"And it was two hours and fifty minutes, you exaggerating pervert."
She rested her chin on his shoulder, her breath hot and sweet against his ear. "…Carry me past the konbini," she commanded, her voice a little softer now.
"I want melon pan. And a couple of energy drinks." She paused, then added, a little too quickly, "For gaming tonight. Not because someone drained my stamina like a fucking incubus."
Her teeth grazed his earlobe, not quite a bite, but a close, thrilling promise of one. "And if you brag to anyone about what happened in the theater…"
Her voice dropped to a low, venomous whisper. "…I'll recreate the entire scene, but with your phone taped to my forehead, livestreaming the whole thing."
Despite the threat, her arms looped a little tighter around him.
Just for the walk home. Just for now.
Makoto chuckled, a deep, rumbling sound in his chest. He shifted her weight on his back, a comfortable, familiar adjustment.
"You know," he said, his voice a low, affectionate murmur, "despite all that…"
He rocked her slightly as he walked, a playful, gentle motion. "…you're my cutest, most precious stepsister in the world, Yuna."
Yuna went completely still on his back.
"One honest compliment, as part of our new deal." He winked and hummed.
For a long, silent moment, the only sound was the distant city traffic and her own shaky exhale against his neck.
"…Shut up," she finally mumbled, but her arms tightened around him, a silent, possessive gesture.
Her face pressed into his shoulder, hiding her expression. "You don't get to say shit like that after you just ate me out in public."
She nipped at his ear, softer this time, almost playful. "And you're the worst brother in the world." A beat of silence.
Then, so quiet he almost missed it, a raw, unguarded confession: "…But you're mine, though."
Her legs kicked lightly against his sides, a silent, impatient command. "Now hurry up. I need to shower off your spit before we can start sewing those cosplays."
But she didn't let go of him the entire way home.
He dropped her off in front of her room, the familiar, domestic setting a strange, jarring contrast to the events of the afternoon.
"Regroup in… fifteen minutes in the living room, then?" he said, his voice a little breathless.
He looked at her, a playful, challenging glint in his eye. "And remember to wear the silly unicorn pajamas we bought."
He showered quickly, the hot water doing little to calm the thrumming in his veins.
He put on his own matching unicorn pajamas, a ridiculous, fluffy blue monstrosity, and brought his laptop out to the living room to wait for her. A goofy, lovesick grin was plastered on his face.
Yuna emerged exactly fourteen minutes later.
Her damp hair clung to the oversized unicorn hoodie (complete with a ridiculously floppy horn) that she had insisted was "ironic" when they'd bought it.
The pajama pants rode up her calves, revealing the fresh, angry-looking kiss marks on her inner thighs from their cinematic adventure.
She was a walking, talking, beautiful contradiction. All his.