Animalize! Demonium - Part 1

Mamiko stifled her cries.
	As she climaxed she slid the novelty demon dildo home and squeezed hard, sending its thick fluid to mix with her own. She fell back on her bed and lay in the dark, naked and exhausted, leaving the dildo in and her legs spread out as she savored the wet warmth filling her.
	It still wasn't enough to make her forget. Some nights ago she had announced her intention to drop out of university. While Mom had tried to be understanding, Dad wanted her out of here fast. Whimpering, Mamiko stroked her raw vulva and clitoris to dispel the memory.
	Soon she realized the raw, tingling feeling was spreading to the rest of her body. Now everywhere she touched she felt a pleasant jolt. She lost herself in pleasure again, uncontrollably moaning and writhing and groping herself all over. The tingling grew especially strong in her back.
	When she sat up and felt behind her, she found the edge of something strange. As she began to wonder what the thing was, it stretched and expanded to full size, arching her back violently. It was a pair of tan and pink leathery bat wings, spanning as wide as her own height. Mamiko had just enough time to look back at them in bewilderment, but then buckled and squealed for joy as the powerful sensation spread to every part of her.
	Wave after wave of ecstasy washed over Mamiko with each step of her transformation. Her ears stretched like mochi dough into elven points. Bony spikes erupted out of her wavy brown hair, curling into goat's horns. And along her lower back emerged a ridge that swelled into a fleshy arrow-tipped whip.
	When it was over, the pleasure subsided slightly, just enough to let Mamiko take the dildo out, stand up, and take stock of herself. Even as her mirror showed a monster out of a fantasy manga, the constant flutter in her heart and warm desire in her loins made it hard to care. She marveled at the dance of her tail as she moved and turned about. She tried wrapping herself up like a sleeping bat and sighed as she found it warmer and comfier than the heaviest and softest blanket.
	Then Mamiko realized she was seeing all of this in the dark. There was a faint purple tint to her new night vision. Silhouettes of everyone around her, even through the walls and floors, glowed varying shades of pink. By some new-found instinct the brighter ones called out to her: they were the ones who most needed her care, and she could sate her own burning desires with them too.
	Still naked and horny, she tiptoed out into the hall. Like a moth she followed the biggest, brightest glow into her little sister's room.

	As Mamiko approached Kumiko's bed, she giggled at what she saw through the covers. Lifting them revealed Kumiko's sleeping form with one hand suspiciously in her pants.
	"Naughty girl," she scolded with a grin.
	Slowly, carefully, Mamiko slid the naughty hand out and found the fingertips slightly moist.
	"Hmmm?" purred Mamiko. "And who's in your dreams tonight?" To find out, she lay at Kumiko's side, close enough for her horns to receive her sister's thoughts.
	She lay peering into Kumiko's dream for a while. She saw the pink aura around Kumiko brighten as the object of her lust started to appear to her. When Mamiko saw who it was, she gasped in surprise, a little too loudly.
	Kumiko's eyes opened, then narrowed. "お姉ちゃん？" ("O-nee-chan?")
	Mamiko smiled her brightest smile and whispered "Hi."
	"What do you want?" Kumiko sat up and rubbed her eyes.
	"Just..." Mamiko shrugged. "A little bit lonely."
	"Huh?" Kumiko squinted at the glow of the digital clock. "You know, it's really late for jokes."
	"I'm serious. And I know there's someone you want too. Right?"
	These words shot Kumiko in the heart. Too honest to outright deny it, and noticing the moistness still in her fingers and underwear, she flushed and turned away. In Mamiko's vision, her pink aura flared a little brighter again.
	"What do you care?" snapped Kumiko. "That's my own business. Leave me alone!"
	"No, no! I was a little bit surprised, but you two would be totally cute together!" Mamiko stroked Kumiko's fluffy brown hair with a loving hand. "I know. お姉ちゃん can hook you up right now."
	"Stop it!" Taking her sister's kindness as mockery, Kumiko threw it off. "What gives you the right to know or do anything? Just get..." She stopped when she turned to her sister and got a good look. Her eyes now adjusted to the dark, she saw Mamiko's naked body, leathery wings, wicked horns, whip-like tail...and eyes, glowing faintly purple.
	"お姉ちゃん...what--"
	Each pupil shone a bright pink light into Kumiko's, spinning her brain like a lotto wheel and turning her muscles to warm jelly. She started to slump forward and murmur incoherently.
	"Shh, shh." Mamiko eased her back down onto the bed, kissing one cheek while caressing the other. "I'll take you to your someone and you two can play all night long." She started to help Kumiko out of her pajamas. "But first warm up with me."
	Once Kumiko was naked too, Mamiko sat with Kumiko's head between her thighs. Then Mamiko started to grind her mound back and forth against Kumiko's nose and mouth, gently and then rapidly, breathing heavily, her folded wings shaking in sync with her hips.
	Kumiko sputtered weakly in protest at first. But by the time her strength returned, the scent of her sister's lust so intoxicated her that she couldn't help pulling Mamiko's thighs closer and digging her tongue into the sweet, hot syrup. "Ooh!" Mamiko laughed in delight. "You're doing so good." She slowed down to let Kumiko drink deeper.
	An incidental brush of Mamiko's tail against her back gave her an idea. She twisted around and grabbed the devilish tip, then leaned back to press it between Kumiko's legs. Kumiko wailed at the wiggly thing tickling her pussy, and then cried out as Mamiko guided it inside, making Kumiko’s legs twitch with excitement. In return, Kumiko's licking and sucking grew in intensity.
	Higher and higher both sisters moaned, and Mamiko's hips began to pick up speed again, until she reached her peak and a fountain of luminescent nectar blasted Kumiko in the face. After a moment of cooldown, Mamiko backed off and bemusedly watched Kumiko savor and swallow every drop of the pink glowing mess.
	When Kumiko was done, she whined and pawed Mamiko for more like a little hungry puppy. "Whoa! Easy, girl," Mamiko said, holding her off gently. "Save some for..." She trailed off on seeing her juice's stranger effects on her little sister.
	Kumiko did become a puppy - partially. Before her sister's amazed eyes, she did a canine howling-at-the-moon pose as her scalp squeezed out two quivering brown flaps, and a fluffy mass wriggled from her lower back. When ears and tail had fully grown, Kumiko threw herself into Mamiko's arms with an excited yap.
	"Oh my God! How cute!" Mamiko gushed. If "God" was a bad word to a demon, there was no sign. She literally took Kumiko under her wing, petting her behind the ears and under the chin, and Kumiko lapped at her face. "Okay. Okay. That's a good girl."
	Then she looked to the bedroom window. "Now let's go play with the one you love, hmm?" Kumiko barked yes and let her tongue stick slightly out of her open mouth. Mamiko went and opened the blinds, then the window. Then she crouched, and Kumiko climbed onto her back just as she had for piggyback rides when she was little.
	Mamiko stood up and shifted to make sure Kumiko was secure. She climbed onto the window sill and leaped with wings spread into the night air. Even on her first flight, and with a passenger at that, her initial unsteadiness was short-lived as the powerful wings carried the sisters into the dark, sparkling sky, towards Kumiko's secret love.