It was equal parts invigorating and enlightening.

Indeed… There was nothing quite like it. That was what Shiroko had discovered. She'd never take drugs or imbibe alcohol or anything harmful like that. After all, she'd worked so hard to maintain her athletic figure — her slim physique and tight, toned body. Such vices were inappropriate for the likes of her.

"Besides," she whispered to herself, "this feels better than anything in the world…"

Making sure that the coast was clear, Shiroko reached underneath her own skirt, and she hooked her thumbs into the elastic of her panties.

She yanked them down to her ankles before stepping out of them, and she stuffed them into her backpack. With an anxious gulp, Shiroko made sure that her bicycle's modifications were accounted for.

She strapped LED lights to the bike's frame.

She latched the basket to the front.

The chain was freshly lubricated.

The dildo was…

Shiroko shuddered — but not from the cold. She eyed the sex toy with fascination, hardly able to believe that such a device had ended up in her possession. She had to remember to thank Hoshino again later for the best stress relief she'd ever indulged in.

Shiroko wrapped her pale little hand around the circumference of the black sex toy, feeling its pleasant heat against her palm. A shiver ran down her spine as she knew this beast would be inside of her in just a minute.

She took pride because she'd kept this a secret from everyone. Serika, Nonomi, Ayane, and even Hoshino… none of her other schoolmates were privy to this nasty ritual of hers.

Being covert like this delighted her. She couldn't wait any longer. Retrieving the bottle of anal lubricant from her bag, Shiroko poured a generous few ounces over the turgid toy and the seat beneath it, thankful that she'd had the foresight to attach the dildo to the cushion itself. It wasn't going anywhere but deep inside her; there was no risk of falling.

Shiroko slipped the backpack over her shoulders again, before climbing onto the bicycle. Exercising caution, she hiked up her skirt and slid the slick dildo against her ass crack, biting her lip at the intimate sensation of something so thick, so heavy, so powerful… gliding against her body like this. It titillated her; she felt like such a slut when she behaved in this manner, away from scrutiny. It was dark enough, and late enough, that no one should disturb her while she had her fun.

Coated in all that helpful lube, the dildo glistened as Shiroko slowly but surely sat down. She worked the sizable toy into her shaking lower half, eventually swallowing the entire length of the faux cock with her juicy bubble butt.

"Nngh…! Hah… Yes… Just like… th-that…"

She was a big girl, she thought. She could take it well enough at this point. The first time had certainly been a challenge… but after a couple of weeks of this nighttime ritual, she felt like much more of a sexpert. Hoshino's insights had proven invaluable.

With that in mind, Shiroko started pedaling. Steering the bike carefully onto the road, she began to ride to tonight's destination.

As she rode her bike — as she pedaled ahead and cycled with the strength of her robust legs — Shiroko would sway up and down, back and forth…

And as she rode her bike, she rode the dildo, too. Hidden beneath her pleated skirt, the toy sternly worked in and out of her cushiony ass like a piston, causing the student to moan and groan in pleasure. The lubrication helped as much as it always had, making it easy for the sex toy to slide in and out of her rear end with little effort.

Shiroko cursed under her breath. Sweat already beaded on her forehead as she pedaled along, feeling the warmth and wetness in her loins grow with each passing minute.

I can't believe I'm doing this… she thought. I'm so bad… But… I can't stop…

There were no other cyclists to be found at this time of night. The occasional passerby, sure, but no one that paid her too much suspicion. Shiroko was Abydos' resident cyclist. At a glance, there wouldn't be anything suspicious with the student's activities.

If they only knew, though, just how depraved she really was…

The cushion beneath her squeaked in rhythm with her bumping and grinding. Pedaling around a corner and curling her body slightly, Shiroko's tongue dangled from between her little lips as she whimpered lustfully, worried that someone going on a night walk might hear her.

However, she was tempted to slide a hand down to her folds and finger herself as she rode. It was a dangerous line of thinking. Dangerous, but spine-tingling.

I should just get there first…

Not even halfway there, Shiroko struggled to keep her tongue in her mouth. She drooled over herself as she rode onward, her entire body shuddering from the lust and the euphoria of pleasuring herself like this.

Guh… Doing it at home just doesn't cut it anymore… she thought worriedly. In hindsight, she should have expected to gain a proclivity like this, being the little daredevil that she was.

Her saliva soaked into her shirt. Her entire body grew flush from the temperature difference; the heat of her passion, coupled with the cool, gentle breeze that brushed across her form. Goosebumps formed over her bare arms and thighs; the exhilaration got her heart pumping and her teeth chattering.

Up, and down, and up, and down…

Back, and forth, and back, and forth…

Squeak… squeak… squeak…

Shiroko moaned aloud as she slammed her ass against the bike's cushion and took the dildo all the way once more. With her hand wrapped around the gearshift, Shiroko kicked it up a notch, feeling the burn in her thighs and her calves as she zoomed toward a bumpy road.

Thump thump thump!

The bike — and by extension, Shiroko — bounced as she darted right over cracked asphalt and rugged terrain. Another slutty moan slipped from the student's lips, and she grinned mischievously as she cycled past a 24-hour convenience store.

Maybe I should make a pit stop?

Another bounce changed her mind.

I'll do it tomorrow night, heh…

She could see her destination up ahead. Beyond the shrubs and the grass moist with dew: the fountain at the center of the park that had served as her special spot for the past week and a half. But could she make it to the bench before her orgasm? Would she break this self-imposed rule?

I can make it…

Shiroko whimpered, her body quivering as she pedaled even faster. As the park bench came into view, Shiroko could feel a gust of wind brush beneath her, and it hiked up her skirt!

Were this to happen during the day, there would be no doubt that someone would have seen Shiroko's bare ass and pussy; her slick and glistening nethers would have been on full display for any passerby. Given the nighttime atmosphere, however, there was no one around to witness this depravity. No one was around to see how Shiroko's pleated skirt flapped up, revealing the manner in which she rode her dildo; how it pushed in and out of her ass with every thrust and bounce of her booty.

This, alone, was what brought her to a premature orgasm. Shiroko squealed with pleasure as she came hard, covering her mouth and biking one-handed to the bench, slowly but surely. Her entire body trembled as if a tremor had passed through her; the bicycle's cushion squeaked and groaned as she humped it nice and hard, feeling her asshole clench and wring around the fat dildo that invaded her slender, supple body.

By the time the bicycle stopped, Shiroko is panting from the euphoria of her climax. She was slipping into a wonderful afterglow, welcoming huge gulps of air into her lungs. Planting her feet on the ground, on either side of her bike, the slutty student Shiroko slumped against her handlebars, humming and moaning with great satisfaction.

"Hah… I almost made it… I was so close," she whispered. Her chest rose and fell with her heavy breathing, and after a minute of trying to compose herself, Shiroko decided it was time to give her sore ass a break.

Cautiously, Shiroko lifted herself off of the bike's cushion, working the slimy dildo out of her rear end. She worked more and more inches out of her tight, greedy asshole. Eventually…

Pop!

The entire thing came out with a sudden suction sound that left Shiroko blushing beet red. The moan that left her lips, too, was wholly involuntary — same as all the others.

"Gah… I'm so… Depraved," she remarked, once again looking around and spotting no one around. In the wake of her climax, she couldn't help but feel a strange mixture of liberation and shame. More than anything, however, Shiroko's legs were wobbly; everything below the waist felt like gelatin, and this was most clear as she stumbled bow-legged to the park bench, her back door gaping wide beneath her skirt and winking with apparent desperation to be filled once more.

Maybe it was a trick of the streetlight up above, but Shiroko could swear that she saw the dildo steaming from when she was sitting on it. Her skin was hot to the touch, and she was sweating. I'll just rest here for a little while, she thought to herself, dropping her backpack beside the bench only after taking a water bottle out of it.

She took a swig of water before emptying the rest over herself, sighing aloud with relief as the cold liquid helped to cool her down.

Dripping wet and satisfied, Shiroko sat down on the bench and closed her eyes with a wicked little smile.

"Now that was a workout," she whispered pridefully.

And then — without really meaning to — Shiroko slipped into a little catnap, snoring softly beneath the streetlight and glistening wet. She slept unaware of the last time she'd felt such satisfaction. Unaware of the last time she had this much fun.

Unaware that someone, somewhere, was watching her with intent.