The shiny, seamless white underwear hugs the curve of Ryuuko's bottom like a second skin as she examines herself in the full length mirror. Jewels glitter along the seam under the blinding crystal ceiling light when she glances over her shoulder and catches Satsuki staring. Ryuuko looks even better embarrassed, with pink cheeks and a flat tummy.
"Those are mine," she says, trying to swallow the bewilderment lodged in her throat. "You're wearing my panties."
Ryuuko covers her bare chest, naive expression betraying the silky underwear below her navel. Is this someone's idea of a joke? Instead of a heart, there's a steel rod in the middle of Kiryuin Satsuki's chest. Stronger than tissue, hidden and locked like a bank vault, it bleeds for her little sister alone.
"This is fine," Ryuuko blusters. "Your my..." She sputters, but in the end she can't force the word out. She swallows hard and scrunches her eyes shut. "We're related, now!"
The wind blows when Satsuki speaks, clear and resolute. "So you feel entitled to stealing my clothes?" She descends upon Ryuuko like a viper, looming over her shoulder. Her fingers graze Ryuuko's hips to pull her in close before leaning down to whisper in her ear. "It almost suits you."
Satsuki grabs her by the rear, fingers twisting around the underwear and yanking it up her crack. Ryuuko shudders, hot all the way to the tips of her ears, and tears herself from Satsuki's arms. This is how Satsuki melts, slow and soft as hot candlewax.
"Like anyone could ever pull off something this flashy!"
Surprise sealed shut, Satsuki recollects herself, lifting the remainder of the outfit from the floor with a sly smile. "Let's find out." The matching top dangles seductively from her painted nails. "Unless you're afraid you can't measure up."
In one swift movement, Satsuki pulls the sash from around her own waist, robe slipping from the slope of her broad shoulders and onto the floor, exposing the dazzling clothes underneath. The undergarments are nearly identical, emitting a piercing shine and reflecting light around the whole room.
"Tch, yeah right." Ryuuko shakes her head, taking a rebellious step forward and thrusting out her arm. "As if I'd spend my life living in your shadow."
She snatches the garment and crumples it in her fist before turning away to try and work out how to wear it. It doesn't unhook or have a wire, and the straps criss-cross in a way Satsuki knows she isn't used to.
"I can do it myself," Ryuuko insists, even when the fabric threatens to tear.
Satsuki steps forward and hugs her from behind, staring at their reflections in the mirror. Where their bodies touch forms a molten crease, easy and intimate. Satsuki can feel each vertebrae when she brushes her fingertips along Ryuuko's spine.
"What!" Ryuuko's eyebrows shoot to the top of her head as she struggles to comprehend the situation. "What are you doing?"
"Helping," Satsuki says, lips twitching, almost threatening to smile. "We're related now, right?"
Satsuki doesn't stop to tease or dawdle, but her thumbnails graze Ryuuko's chest when she pulls the top down over her head. Ryuuko covers herself reflexively, nipples at attention beneath the layer of spandex. Satsuki considers sliding her hands underneath, but changes her mind at the twist in her sister's features.
"I'm cold," Ryuuko snaps, as if to absolve herself from the shame.
Satsuki swallows and shakes her head, before pulling away with a wry smile. "I was wrong," she admits, before turning back to her sister with an appraising look. "It suits you best after all."