My Sister Turns Into a Yandere at Night

"What? You want me to cosplay a little loli?!"

Lu Lingyue stared at the costume in her hands, voice trembling with disbelief.

"Exactly! This look suits you perfectly now."

Lu Xiaoxue pushed the outfit closer, her azure eyes glinting with mischief.

"But I hate interacting with crowds."

"Being a beauty influencer just means posting cute videos online," the silver-haired girl countered smoothly. "No real socializing needed - perfect for you."

"F-fine..."

Clutching the Klee cosplay costume, Lingyue shuffled into the dressing room.

Huffing and puffing.

The petite girl struggled with the intricate red ensemble. No matter how she contorted against walls, knelt dramatically, or flopped sideways - that damn back zipper remained elusive.

Final attempt: She flopped onto the floor, attempting to reach the zipper with her 'divine right hand'.

"Need help?" Xiaoxue's angelic face peeked through the curtain.

"N-no!" Lingyue froze mid-crawl like a startled kitten.

Ignoring protests, Xiaoxue glided in and zipped the costume effortlessly. "All done~"

"Th-thanks..." The blushing girl accepted the hand up.

"By the way..." Xiaoxue leaned dangerously close, breath ghosting over Lingyue's ear. "...you flashed me earlier."

Twenty years of male life had ill-prepared her for skirt etiquette.

"White cotton," the silver-haired temptress purred, close enough to share eyelash counts.

Lingyue's toes curled hard enough to excavate a mansion. Death-by-Xiaoxue's-bosom seemed preferable to this humiliation.

When sufficiently amused, Xiaoxue finally stepped back. "See? You're born for loli roles!"

The mirror reflected a living anime character - dewy skin, doll-like proportions, and eyes sparkling with innocent confusion.

"Missing something..." Xiaoxue tapped her chin. "Ah! The wig and makeup. Let's start with cosmetics first."

As brushes danced across her face, Lingyue studied her mysterious benefactor. The usually aloof novelist had transformed into an overaffectionate fairy godmother. Was femininity this powerful?

"Done!" Xiaoxue booped her nose. "Now for promotional content."

Poses. Props. A video of her tossing imaginary "jumpy dumpty" bombs.

"These will trend for sure." Xiaoxue transferred files via WeChat - their first ever message exchange.

"Th-thank you..."

The novelist's dimpled smile held predatory undertones. "My pleasure~"

As midnight approached, Lingyue lay wrapped in jasmine-scented sleepwear, awaiting her elusive system.

Just as drowsiness claimed her -

"MAKE WAY FOR THE QUEEN!" Blaring rock music announced the system sprite's arrival.

"Are you trying to give me heart failure?!" Lingyue jolted upright.

Ignoring complaints, the system demanded: "Have you decided your career path yet?!"