Ethan plonked himself down on his bed. He had a mission, the lads would be picking him up tomorrow for a mostly unscripted holiday tour of the party venues of Europe. He wasn't sure when they'd get back or where they'd be staying. What they did give him was a checklist of all the naughty things he had to get up to. It was mostly the standard affair of getting with x number of girls. Acquiring x number of panties, shagging certain body types... he was not looking forward to ticking off the chubby chaser box. However, this year there was a surprise addition one that needed him to prepare things in advance. For this year a new box was added to the list. He would have to shrink himself and have one of the lads gift him to one of the group of girls that would be heading out with them. They only agreed to this new addition given that they knew the girls so the chances of something bad happening was considered negligible.

Clothes were packed, passport check, charger check, shrinkme app... hmm better get that set up now, he thought. He rushed through the various options clicking away, increased durability, reduced oxygen requirements. He saw the timed automatic enlargement option, but figured that could wait till he knew how long he was supposed to be 'gifted' for. Hmm, time for a test run. Ethan's fingers trembled as he pressed the final button on his newly downloaded app. The screen flashed with a bright, almost blinding light, and he felt himself shrinking. He glanced down at his phone, confirming the message: "Shrink complete. You are now 6 inches tall." His heart raced, both with excitement and anxiety. It worked, but what if something went wrong? I should proba...

Before he could react further, the door to his room swung open. "Ethan, dinner's ready!" his sister Lily called out, her voice echoing through the small space. Ethan panicked, completely freezing up. Lily, despite his size spotted him immediately. Her eyes widened in shock. The pair stared at each other, with neither moving an inch. Suddenly, Lily's brain had parsed the situation and a mischievous smirk grew on her face.

"Ethan? Is that you?" she asked, bending down to get a closer look. Her face was a mix of surprise and something else—something darker. "You know, I always thought you were kind of a shortie, but this... this is perfect."

Ethan's mind raced. "Lily, please, I just need to reverse this. It was an accident! I was just testing out that new shrinkme app that everyone has been talking about."

She ignored him, reaching out with a manicured finger to prod him. "Accident or not brother mine", her eyebrows raised and a shark like grin grew on her face, before she continued "you're mine now. Imagine what I can do with you like this."

Ethan's fear turned to horror as he realized what she meant. "No, Lily! Please!" But it was too late. She scooped him up, her grip firm and unyielding.

"O, don't worry," she whispered, her breath hot against his tiny form. "I'll make sure I won't be the only one enjoying myself."

Ethan struggled, but his efforts were futile. Lily carried him into her bedroom and closed the door behind them. She placed him on her bed, her eyes never leaving his. "Stay still," she commanded, her tone brooking no argument.

He watched helplessly as she opened a drawer and pulled out a not so small, velvet bag. Inside were various sex toys, each one more intimidating than the last. Lily selected a clear, cylindrical tube with a suction cup base. "To think, after Joe chickened out I didn't think I'd be getting any use out of this during the hols.... This will be perfect for you," she said, her voice dripping with anticipation.

Ethan's protests were cut off as she picked him up again, her fingers pressing him into the tube. He tried to resist, but the confines of the device left him no room to move. Lily smiled, pleased with her handiwork. "Now, let's see how you like this," she said, attaching the tube to the base and positioning it against her crotch.

Ethan's heart pounded as he saw her wet panties pressing against his plastic shell. She moved slowly, teasing him with her warmth and scent. "That's it," she cooed, her voice a low murmur. "Feel me, Ethan. Feel every inch of me."

His body betrayed him, responding despite his fear. Lily sensed his reaction and laughed softly. "Good boy," she purred. "Let's give you something to really enjoy."

She shifted, her movements deliberate and slow. She placed him back on the bed, then slowly turned and bent at the waist inching her now sodden underwear down her generous curves. Ethan knew he should be trying to escape or at the very least look away, but he was completely enthralled by the scene in front of him. Yet, before the panties could hit the ground a voice hollered up the stairs "just what in God's name is keeping you kids! Mum called you for dinner a good fifteen minutes ago, if butts aren't on seats within five mins Sandy is going to be eating well tonight". A look of pure relief appeared on Ethan's face, while a look of equal frustration appeared on Lilly's. "For fucks sake" she breathed out. Then looking at Ethan that grin came across her face again as she shouted back, "OK be right there Dad, but Ethan has already left for his tour with his buddies. They moved up their plans so he shot off this afternoon, guess he didn't think to message you... typical Ethan". She looked at the growing confusion on Ethan's face and giggled softly, "you're not getting out of this so easily lil bro, when have our parents ever not believed me? Plus you've conveniently provided me with your phone, it's almost like you wanted me to claim you." She quickly pulled up her underwear and put on some short shorts. Then without a further word to him picked up the stuttering Ethan and dropped him in her toy bag. After zipping it up she left it on her bedside, whispering "don't fret, big sis won't be long. Then we can pick up where we left off" She left the room chuckling to herself this holiday was beginning to look up.

Ethan was left to wait in the darkness, with his movements restricted by the... no not going there now he thought. His thoughts instead wandered to where he should be and what if he didn't get out of here he'd be missing. He'd been looking forward to this trip for months. After he found out about this damn shrinking box he'd even been excited about it. Already having planned out who he'd be gifted to. "Fuck" he grunted, surely this was all a perverse joke. His sister was never really going to follow through. I mean sure she and well the entire family was always open... too open with their sexuality. Their parents were to blame for this, far, far, far too open with the goings on in their sex life. If he ever stuck in rich he already knew a lot of his earning would be diverted to pay for therapy. On the one hand it was titillating growing up round a milf who often wore what most would consider scandalous clothing around the house, then later on his twin sis picked up the habit from her. Though mum did it in a blase manner, Lily knew exactly what she was doing. Mum and Dad never believed him when he said anything, but she got a kick out driving him up the wall. Of course, any hormonal teenager would use it for his spank bank.. it wasn't his fault. His family was just not... normal.

Ethan was broken out of his reverie by the sound of the door opening. Play it cool he thought, beg if you need to, anything to get out of this situation and back to his bedroom and full size. As the zip sped by light shone into the bag once more. Ethan's strange reality was brought back into focus as he saw a host of sex toys surrounding him. His sister already stripped down to her lingerie, his stomach tensed, if this was a prank his twin sis had a future on Broadway.

Lily purred "right where I left you" she seductively smiled at him. "Now no need for foreplay, dinner with Mum an Dad while thinking of what's waiting for me, for us. Well I'm already as hot an steamy as I'm going to get." She pulled him out of the bag, then hastily made it over to her bed throwing off the covers. She got on the bed with legs spread, lifting Ethan up to her face she teased him once more "but, they do say that seeing is believing, the proof is in the pussy pudding". Ethan saw her shifting about, but couldn't turn to see what was happening. There wasn't really any need since he swiftly began his journey south. Through the tightly packed cleavage, over the lacey black bra, down a taunt fit stomach. Ethan soon arrived at his destination.

Ethan tried speaking up and protesting, but Lil was already raring to go. The head was quickly put in place and started circling her lips pressing ever forward. Till that moment when everything opened up and suddenly he shot forward. While the head of his personal fuck chariot had sunk into her, his head was still just outside. He wasn't sure what to say or do, the sight and smell was numbing his mind. A loud moan rang out and he slipped the rest of the way in. Jesus she wasn't kidding about being ready, it was a fucking sauna in here/her. Ethan could feel her muscles clenching around him, pressing against the hollow dildo. The sensations were electric and overwhelming, for both of them. "Ah, that's it," she moaned, her voice vibrating through the tube. "Take it all... Ethan. I'm taking everything you can give me."

Ethan's mind whirled as he tried to process the situation. He had never imagined anything like this, never wanted it. Well, at least not like this. But here he was, trapped, reduced to a fuck stick, and used by his own sister. Worst of all, part of him was enjoying it.

Lily's rhythm increased, her hips thrusting more forcefully. Ethan could barely think as her movements sent waves of pleasure through him. "Harder," she demanded, her voice breathless. "Faster, Ethan. I want to feel you."

Her words drove him to the edge, his own arousal mounting rapidly. Lily's hands gripped the balls of the tube, her nails digging into the material. "Come for me, Ethan, come with me" she whispered, her voice a sultry command. "Come for your sister."

Ethan couldn't hold back any longer. He didn't know when he had started but he was rapidly stoking away. His body shuddered, his release exploding within the confines of the tube corresponding with Lily's internal muscles rhythmically squeezing his ride. Juices flowed past his face to a chorus of moans. On the outside Lily's eyes gleamed with triumph as she felt his orgasm from the sudden ceasing of his manic movements. "Good boy, good boy" she repeated, her voice filled with satisfaction. Ethan breathed in and out heavily, his mind trying to switch back on. This experience, this experience was well it was. Hmm he felt amazing, his body despite the heavy workout felt completely lax, almost boneless. Yet, on the other hand he felt shame for having been used like that by his sister of all people, guilt he had definitely stopped being a helpless spectator and actively participated in making both of them cum. If asked he wouldn't have known what to say.

But her plans weren't over yet. She detached the tube from the base, placing Ethan on her nightstand. "Stay there, don't go anywhere" she ordered with a smirk, her tone leaving no room for disobedience, though they both knew in his capsule form, he was going nowhere. "We're far from done."

Ethan lay there, exhausted and humiliated. He had no idea what Lily had planned next, but he knew one thing for certain: his life had just taken a strange, very dark and twisted turn.

As Lily left the room, Ethan's thoughts raced. How could he escape this nightmare? How could he get back to his normal size? And most importantly, how could he make sure the rest of his family and his friends never found out about this?

But before he could come up with a plan, Lily returned, carrying something unexpected. "Time for round two," she announced, her voice filled with malicious glee. Her hand smacked a suction cup base to her bed's headboard. As she picked him up and attached him to the base, Ethan got another view of his sister's assets. Damn why did she have to be his sister, he'd take anyone else.... especially if they came as equipped as her.