He couldn't sleep. The last twenty-four hours were stuck on a loop in his head. The massage parlor, the Ganyu cosplay, the blackmail, the panties.
Yeah, especially the panties.
With a groan, Makoto gave up and reached into his sock drawer. His fingers brushed against the soft, lacy fabric, and a shameful jolt of electricity shot through him.
He pulled them out. They still smelled like her, sweet and a little musky. It was pure Yuna.
His self-control, already shot to hell, just snapped.
He wrapped the damp fabric around his throbbing cock and started stroking himself, his movements rough and desperate.
His mind filled with the image of Yuna in that lingerie she wanted, a private show just for him. He groaned, the fantasy taking over as he came with a shuddering, explosive force.
CRASH!
The sound of his bedroom door slamming open cracked the silence like a gunshot. Yuna burst in without knocking, hands on her hips, a complaint already on her lips. "Big bro! I told you to stop watching porn or making weird noises when I'm trying to slee—"
She froze. Her eyes went wide, taking in the whole scene: Makoto, half-naked on his bed, her panties wrapped around his still-twitching cock, his fresh cum dripping onto the sheets.
The silence was terrifying. Then, a slow, wicked grin spread across her face. It was the look of a wolf that had just cornered a rabbit.
"Ooooooh," she cooed, skipping closer. The oversized shirt she wore rode up, showing that she wasn't wearing any panties herself. "So this is how you burn the evidence?"
Her hand snaked between his legs, her fingers closing around him right through the damp, cum-stained fabric.
The touch was a sick mix of shame and pleasure.
"Get out!" Makoto hissed, his voice a choked whisper.
He wanted to scream, but their mom was sleeping just one room over. "How many times have I told you to knock?"
He tried to bat her hand away, but his touch was weak. "Just get out! I couldn't sleep, so I needed some... relief."
"Nuh-uh," Yuna shook her head, plopping down on his bed. She was in charge, and she knew it. "I'm not going anywhere until we have a little chat."
She leaned back on her elbows, a casual move that made her shirt ride up completely, exposing her bare, glistening pussy. "So, big bro was getting off to his little stepsister's scent?"
She giggled, the sound grating on his nerves. "That's sooo pervy!"
Her finger traced slow circles on his thigh. "But since you clearly can't sleep without my help."
She bit her lip, her eyes raking over him. "How about a live show, right now? Just 30,000 yen (~200$), and I'll finger myself while you watch."
Makoto's jaw dropped. The sheer nerve of it was stunning. "Are you kidding me? I don't even have money for food. Did you see the ramen cup I was eating? "
Yuna's pout was pure theater, but the mischievous spark in her eyes never left. "Fine," she sighed, flopping back on his bed. "Since you're so broke..."
Suddenly, her legs spread wide, and her fingers trailed down to her glistening entrance. "I'll give you a free preview."
She moaned, a loud, obscene sound, as two fingers slid into her tight, wet hole. Her other hand pinched her nipple through her shirt.
"Look how wet I am just thinking about you sniffing my panties, big bro."
"Fuck off," Makoto grunted, but it was a weak protest. "I don't want to watch you."
But he couldn't look away. His eyes were glued to her hand, to the way her fingers moved. He found himself leaning closer, drawn in by her scent.
"Liar!" Yuna giggled, pulling her glistening fingers from her pussy and shoving them at his mouth. "Open wide."
He instinctively parted his lips, and she slid her wet fingers inside. "Taste that?" she moaned, grinding her hip against his thigh.
"That's how turned on I am watching you be such a pervert."
Before he could react, she grabbed his hand and shoved it between her legs, pressing his fingers right against her slick, throbbing clit.
"Go on, big bro," she breathed, her voice thick with arousal. "Touch me properly. Or I'll scream for mom right now!"
The threat hung in the air like a bomb. His mind raced. He could see it all: the scream, the footsteps, the door opening on this... this disaster. He was trapped.
"We can't," he whispered, a pathetic plea against his own rising desire.
"This is so wrong." His fingers trembled against her, slick with her wetness. They started to move on their own, tracing her folds, circling her clit.
The difference between what he was saying and what he was doing made him sick.
"Can you... at least put on a cosplay, please, Yuna?" It was a desperate, stupid request, a last-ditch effort to put some kind of fantasy between them.
A predatory glee lit up her eyes. This was a negotiation, and she had all the power. "Ganyu costume? That'll be a 30,000 yen deposit!" she chirped, shoving his fingers deeper inside her.
"But since my big step bro is broke..."
She scrambled off the bed and sneakily walked back to her room. He heard her rummaging in her closet before she came back, wearing nothing but the messy blue Ganyu wig from the parlor.
It was a pathetic, half-assed costume, but it was enough.
"There! Happy?" She struck a lewd pose, spreading her legs wide on his bed, a grotesque parody of the elegant character. "Now get back to work, big bro."
Her hand snaked down to rub her own clit as she moaned, her voice shifting back to that scarily good Ganyu impression: "The traveler's fingers feel... mngh... so skilled."
Makoto's mind went blissfully blank. He focused on the fantasy, on the feel of her under his touch. "Not my stepsister, not my stepsister…" he chanted in his head.
"That's right," Yuna purred in her sultry Ganyu voice, arching her back. "I'm Ganyu... your devoted secretary."
She grabbed his wrist, guiding his fingers deeper inside her. "Mmph! The traveler knows exactly where to touch..."
Her hips bucked, and for a second, the Ganyu persona shattered. "Fuck, you're making me so wet, big bro!" she gasped in her real voice.
She caught herself and switched back, moaning, "Please... Ganyu needs more. Make me cum on your fingers, dear traveler."
Her pussy clenched around him as she ground desperately against his palm, the blue wig askew on her flushed face.
It was too much. His own control was a distant memory.
"Let's cum together, Ganyu," he growled, his free hand stroking his own cock with frantic speed. He leaned in and crushed his lips against hers in a deep, desperate kiss while his other hand kept working her.
Yuna moaned into the kiss, her tongue tangling with his. "Mngh. Traveler's... so good to Ganyu," she panted between sloppy kisses.
Suddenly, she tore her mouth away with a sharp gasp.
"I'm... I'm cumming!" she shrieked in her real voice, her pussy clamping down on his fingers in a series of violent, ecstatic spasms.
The sound of her real voice, the raw pleasure in it, was the final push he needed. His own cock pulsed violently, hot ropes of cum splattering across her bare stomach.
Panting, Yuna collapsed against him, her sweaty body trembling. "Fuck," she breathed, staring down at the sticky mess they'd made.
Makoto leaned in, his own breath ragged. He gently fixed the crooked wig on her head, a weirdly tender gesture after what they'd just done.
Then he kissed her again, and again, his tongue sliding into her mouth with a new kind of possessiveness.