A/N: Been itching to do more Blue Archive stuff for a good few months now, hopefully this will feed those in need of such lewds~

Do enjoy~

Keep A Secret

It wasn't often Sensei got breaks, not least because of his herculean work load that never seemed to end.

Thus it was a welcome surprise when Rin offered to help him with it and in no time at all cut down on it. Not long after that he received an invitation from Seminar to join them on a small vacation to Red Winter, specifically to one of the several onsen-inns that had been built courtesy of the Hot Spring Development Club going wild with their passion. With his workload already reduced to levels not seen since his arrival he gladly took them up on the offer, and by the next day he, Yuuka and Noa had ventured into the snow-covered territory.

It was actually quite a nice place. Though the people running it were clearly still getting used to the job they were at least earnest and seemed determined to make their stay a pleasant one, and in no time at all they got settled in at their rooms and headed off to the attached onsen. This far away from civilisation they didn't have to worry much about voyeurs, even less so with the bamboo fence erected around the rim... although naturally the girls had one separate from him.

On the plus side, less embarrassing for both of them.

Though the downside – a side he kept firmly to himself – was that he didn't get to see his two cute students in the nude.

Sensei sighed to himself as he strolled out of the changing room, the warm air brushing over his towel-clad form a sharp contrast to the cooler air inside the changing room itself. Though he liked to think of himself as a well-mannered teacher and dutifully guide to his students, there really was no ignoring how hot they all were – nor how eager more than a few were to be in his good books. Frankly he wouldn't be surprised if Shiroko tried to make a move on him, with how often she kept eyeing him when she thought he wasn't looking.

That was a problem for another time though, he could only muse – his worries evaporating with ease as he eyed the onsen itself. It was fairly modest given it was sectioned off just for a small group but it was homely despite that; steam rising from the hot water and intertwining with the bamboo island in the middle of the onsen. Amber lanterns hung off of the walls around the rim and bathed the area in a pleasant glow that reflected off of the water's surface, ripples bubbling up from near the centre where the hot water came from and adding a quiet yet soothing ambience to the moment.

Humming a light tune under his breath Sensei meandered up to the edge and eased one leg down, testing it first before allowing the rest of his body to follow suit. Almost instant a groan fled his throat as he felt the comfortably hot water engulf his lower half; his back propped up against a slanted rock and leaving him reclining in the steaming water – hot enough to soothe but not enough he was worried about being cooked in it. Though he didn't put it past Kasumi to do something like that, if only as a prank.

Huffing at the thought he closed his eyes, just... basking in it, really. Though he had no company to chat with he didn't mind listening to the serene bubbling of water, the distant hooting of an owl, the muffled voices of others further around the onsen. Due to how spaced out the onsens were he wouldn't be able to overhear the girls but he wasn't concerned; both could handle themselves if an attack came. Though he did bemoan the lack of nudity.

Yuuka would probably blush and whack him if she heard him think that, though he had to wonder what Noa would think of his more perverse thoughts?

Then, as if jinxed, he heard the changing room door slide open.

Surprised filled his being and he sat up, words on his tongue – all of which died a swift death as he saw the centre of his thoughts strut into the onsen proper.

''N-Noa?''

''Hehe, good evening Sensei~''

Noa winked playfully his way, her lips curled up into a mirthful look even as her hands pressed her white towel to her front – and damn him but his eyes immediately ran over her figure. Though the material was kept flush to her front, denying him a look at her bare form, he could still get a good glimpse of her bare hips or the side of her breasts, the plump curve jiggling the tiniest bit as she neared.

Only after a good long look did he think to avert his eyes, blushing. ''E-Er, not that I'm not happy to see you, but why are you-''

''-here?'' She finished his sentence with a titter. ''I thought you could use the company. Yuuka doesn't know either.''

''Surely she'll notice your absence?''

''I told her I went to chat with the staff regarding security protocols. Yuuka knows they can take a while.'' Noa soothed.

Sensei nodded, having to swallow the words that threatened to escape as Noa sat down next to him. With him still reclined in the water that left her waist practically at eye-level; her hip bare to his gaze with her towel onto to her front. As if to tease him further she raised her right leg up more, her heel resting on the rim of the onsen and angled just enough to deny him a peek between her legs. Her towel meanwhile remained clutched to her chest with one hand hand, making it slip and cover even less, some side-boob seen... but frustratingly she covered just enough to leave his imagination running wild.

''Tease.'' Sensei grumbled.

Noa giggled then. ''Mm, should a teacher really be saying that about their student~?''

''Says the girl who came in here in just a towel.''

''It's an onsen after all.''

Sensei just grumbled some more choice words, much to Noa's amusement. Nonetheless as the tittering sound trailed off they came to bask in the quiet, the rushing water a soothing ambience to be sure... but by now he could hardly relax when his naked student was right next to him.

A student who soon spoke. ''Can I join you, Sensei?''

''Huh? Yeah, sure-''

He spoke no further before Noa abandoned her towel and lowered her leg. Her hair covered her breasts somewhat but a convenient gust of wind lifted the strands enough to show her pink nipples, complimenting her full, plump breasts. As if unaware of her nudity Noa eased herself down into the water right next to him, smile light and unbothered even as she cosied up against his left side, barely an inch between their hips and giving him an uninhibited view of her.

''Ahh~'' And wasn't her sigh alone erotic too? ''It's so nice...''

''Y-Yeah...'' He coughed out.

Noa giggled at that, eyes narrowed with mirth as she made herself comfortable by his side. The water lapped up around the bottom of her breasts, rising just high enough to hide her nipples but no more, least of all with how busty she was. He tried not to look but it really was impossible, doubly so when she pinched his arm and nudged it behind herself, allowing her to lean against it like it was a pillow.

''...you really like teasing me don't you?'' Sensei muttered then.

Earning another titter from Noa. ''Naturally. Your reactions are so entertaining, Sens-''

In a heartbeat Sensei leaned down, his lips pecking hers. It was a light kiss but instantly made Noa freeze up, her face steadily growing redder by the second and eliciting a chuckle from Sensei himself, his own blush be damned.

''Having the tables tuned doesn't feel so good now huh.'' He dared to tease in return.

His words snapped Noa out of her daze, a sort of surprised giggle escaping her even as she looked upon him with demure eyes. ''M-My, you're even more daring than I expected Sensei. Normally you don't try and get me back.''

''Maybe I just wanted to give you a taste of your own medicine.'' He suggested without much heat.

Noa hummed, one finger to her bottom lip. ''I think I'll need another to really learn my lesson, Sensei. Just don't tell Yuuka-chan you're giving me extra lessons behind her back~''

In response Sensei leaned down, the distance rendered null and void as their lips connected in another, more receptive kiss. Noa cooed into it and snaked her arm up and around his neck, not a shred of hesitation to the act as she lured him in deeper. Far from submissive he dared to wind his left arm further around her until his hand came to settle over her breast; slowly but firmly groping his student and eliciting a little moan from her lips.

The sound, so light yet so erotic, drove him wild. He kept a lid on that wildness but couldn't stop himself from deepening the kiss, his tongue soon prodding Noa's teeth and convincing them to part; allowing their tongues to meet in a slow yet intimate French kiss. The intricate tangling of tongues, the soft groans that escaped Noa as he felt her up – all of it felt so erotic time lost all meaning; resuming only when they drew apart for breath.

Noa though was hardly a submissive girl. A fact he learned as he felt her hand slid down his side, preluding the nimble fingers that curled around his rock-hard cock. He hissed and she tittered in return, all smiles even as her palm pressed up against the back of his shaft and she squeezed it lightly, enough to make him feel it as she slowly stroked him off, handling his cock without a shred of embarrassment.

''Nn... Noa...'' Sensei exhaled heavily.

Groping her wasn't enough anymore, nice as her tit felt in his hand. He released it and ran his fingers down her slender side, slow enough that she could stop him if she wanted – but all Noa did was coo her approval and run her thumb over his tip, teasing a shudder through him. In response he eased his left hand between her creamy thighs and stroked her nether lips, his touch gentle at first but becoming more assertive when it was clear Noa was into it, her moan quiet but oh so erotic in that moment.

Doubly so when his fingers sunk between her smooth petals and into her hot core. Her insides tightened around his intruding fingers and a soft moan lifted itself from her tongue, the arousing notes she reached stifled only by a kiss – though she continued to moan into his mouth, one hand running over his chest and pawing at it even as she squeezed his cock delicately, the stimulation enough to leave him throbbing against her hand.

Noa giggled at that, drawing away from the kiss long enough to flash him a smile before initiating another smooch – their locking lips doing a damn good job of muffling their moans. With nobody around to them though Noa seemed less concerned than he did; the lilted notes passing her lips one by one, each enunciation delicate yet laced with a teasing undercurrent, one that Sensei found himself loving.

''M-Mmph... S-Sensei, you fingers- ah~'' The soft, almost gasped moan made his cock throb in her hand. ''That's it...''

Wordlessly he sunk his fingers between her honeyed lips all the more, finger-fucking his student even as she jerked him off, her motions growing more avid and eager. The water stopped her from moving her hand too fast but her pace was still enough to make the water slosh a bit; the noise lost to the bubbling of the onsen pool further in, masking any sinful sounds from would-be voyeurs.

That was until Noa's hand slowed and her fingers ultimately left his cock, prompting his own to slow. Wordlessly Noa rose to her knees, water dripping off of her naked form and letting him soak in the sight of her bare upper half, his eyes glued to it even as his white-haired student shifted herself onto his lap. Only when he felt her thighs against his own did he snap out of it but even then his focus was hard to break; soaking in every little detail from her slender shoulders to the water droplets atop her chest to the way the water seemed to clear up just the tiniest bit, granting him a view of her nudity in its entirety if only for a moment.

Even when the water fogged back up though there was no hiding the sensation of Noa's hand around his cock, her palm just-barely holding it as she lifted it and eased herself in close, his tip soon pressing against her entrance. Both shuddered and for a brief moment Noa just teased herself on it, her breathing quick as his tip dipped and rubbed against her opening without penetrating, the sensation as pleasurable as it was tortuous, coaxing a groan from his lips-

When Noa finally impaled herself onto him. ''S-Sensei- mn...!''

His hands grabbed her hips in an instant, pleasure a violent force that swept through him as he penetrated his student. With a trembling moan Noa eased herself down deeper, eyes shut and lips pursed as if cementing this sensation into memory – and with how good that memory was, he knew she'd be remembering it for a long time yet. Even still that didn't stop the secretary from rocking her hips and easing herself down deeper, her loins swallowing him up inch by inch until his cock was mostly between her lips.

The lurid heat, the slight wetness, all of it combined to make him grab her ass and yank her down – both of them moaning as they were finally connected fully. Noa shuddered and arched her back, a soundless exhale escaping her before she looked back down at him, cheeks reddening and one wet hand wiping some hair from her face. Not a second later she leaned down and pressed her lips firmly unto his own, the kiss as impassioned as it was maddening.

Keeping one hand on her – very fine – ass Sensei brought his other up to her chest, groping his student and relishing the little moan it coaxed out of Noa. No teases were to come his way though when they drew apart, her eyes half-lidded with lust even as her dark blush spoke to her embarrassment, but without letting it stop her Noa lifted herself up and eased herself back down – her soft hiss only making it hotter.

''Mn, ah... ah... it feels so good inside of me...'' Noa breathed out then, her voice breaking the quiet. ''Mm... have you done this with anyone else yet, Sensei?''

''Not yet.'' He murmured in reply.

Noa smiled at that, a hint of cheek to it but mostly just amusement. ''I'm glad... do I feel nice too, hm~?''

''Don't get cocky now.'' Sensei fired back and flicked her nipple, making her shiver with how sensitive they were when exposed to the cold.

Noa's teasing nature though wouldn't be quelled so easily, even as she worked her hips and impaled herself onto his cock. Sensei couldn't find it in himself to complain though, only a string of grunts and groans escaping him as his cock was sheathed in her searing tightness, every clench of her insides threatening to be the thing that made him bust his nut. He abstained without much trouble but just having her bouncing on his cock was almost dreamlike; the little sloshes of water complimenting her soft grunts and little moans.

Releasing her breast he dipped his hand back beneath the surface of the water to caress her hips, holding her lower half and just reclining as best he could, enjoying the show. Noa tittered and picked up the pace a bit, fully aware how her chest practically bounced in his face from her hurried motions but not minding one bit – least of all when Sensei leaned forth and took one nipple into his mouth, his hard suck making her cry out softly.

A clasping hand muffled her cry but he still heard it all the same, as did he hear the ensuing groan of satisfaction as she grinded herself onto him – quick, back-forth motions that grinded her onto his dick, either not noticing or not caring about how much he was twitching. If anything the way she clenched so tightly around him hinted that she might want it inside, that the thought of an unprotected creampie was thrilling, and in that moment he couldn't deny how temptuous the thought was.

''Noa, I'm close.'' Sensei breathed out, a groan soon following. ''Y-You'll need to, mn, get off soon...''

A giggle answered him. ''Don't worry Sensei, it's a safe day~''

Somehow he doubted that. Perhaps it was how quickly she answered it, how conveniently-timed it was... or perhaps it was the teasing little smile she gave him, both fully aware it wasn't a safe day for her, yet neither truly caring beyond this moment.

Least of all when Noa went back to bouncing on his cock and with a vengeance; the slosh of water louder as she lifted herself up and impaled herself back onto his cock, the warm water around their loins only heightening how good it felt. The slick depths of her loins clenched around him each time she dropped down and he could do nothing but grunt and groan like an animal, his hands running over her hips and thighs when he wasn't gripping them and yanking her down, bringing their loins together as dire need soared up it.

''Shit, Noa...!''

She threw her arms around him, her breasts pressing against his collarbone and lips brushing his left ear. ''Cum inside me Sensei, I-I want it...!''

Her voice tapered, pleasure stealing it as she jammed herself onto him – and suddenly he couldn't hold back any longer. With a soft, strained grunt he blew his load inside of Noa and yanked her hips down as he did so, burying his cock as deep inside of her as physically possible just so he could empty his balls into her womb – spurt after spurt of semen ending up deep inside of her and making her convulse all the more as she came, her cry caught in her throat but still making her spasm all the same, her face euphoric in that moment.

He savoured it for as long as it lasted; their spasms gradually waning as they grinded together and lost their steam, ultimately winding down to a final, panting stop as both came down from cloud nine. Noa moaned into his ear and rested against him fully, her weight comforting as was the sensation of her chest, though he kept that perverse thought to himself. Not that it stopped him from holding her rear and kneading it at his leisure, cementing his student's curves to mind.

Noa giggled as if sensing his thoughts, stealing a quick kiss before pulling away entirely. He silently mourned the loss of her body heat as she retreated, his cock slipping out of her tightness as she shifted to his left, seemingly about to grab her towel.

But naturally Noa could never do the obvious thing; she always had to playfully catch him off guard.

Such as standing up out of the water just to bend over, exposing her curvy behind for him to see.

Sensei hissed out an aroused breath, already rising to his feet. For a moment he just soaked in the sight of her as she shifted her weight from one foot to the other, smiling teasingly back at him and cooing as he groped her rear, his light touch enough to make her push herself back onto his palm. He let that hand fall away though as he shifted behind her proper, one hand stroking his cock before rubbing it along her slit, teasing a little mewl out of her.

And then he sunk in, fucking that mewl into a deeper moan. With a tight groan of his own Sensei clutched onto her hips and buried himself back into Noa, her wetness letting him sink in up to the hilt on the first thrust. The hotness that seized around his length was heaven and her insides felt so hot compared to the cold winter air around them, only further compelling him to rut back into his student the moment he dared pull out.

Much to Noa's delight – her moan short and yelping before she covered it behind a hand, her cheeks burning redder than before. With lust rooted deep within him though he pulled that hand away and bucked his hips once more, his thrusts starting slow but quickly ramping up until he was clapping her cheeks, every forceful impact jolting her forth before Noa shoved herself back onto him with a moan.

''Mm! Sensei, you're being so rough~'' Noa managed to get out, her little giggle melting into a whine when he rutted deep into her. ''I-I like this side of you~''

Rather than respond with words he did so with actions – namely slamming himself into Noa's naughty cunt. The rough slap of their flesh echoed but in that moment he didn't give a damn; grunting like a wild animal as he took Noa from behind, every thrust driving him deep between her lips and into her clenching core. Noa whined in reply, hands clutching at the edge of the onsen even as he pounded her so relentlessly, the lurid smack of flesh making her gasp and pant.

And then yelp when he grabbed her breasts, using them like handholds to pull her back towards him. Warmth burned her cheeks but only moans slipped past her lips as he continued to fuck her like that, holding her close and railing her like she was the last woman on the planet – his cock stuffing her tightening depths to the brim, With hands over his own Noa whimpered and shoved herself back onto him, impaling herself on his cock with equal haste; chasing the building high.

''You're so damn hot it's unfair...!'' Sensei growled in her ear and gave her breasts a squeeze, relishing her low moan.

Words failed him beyond that; unable to truly vocalise how wildly horny Noa made him, how perfect every inch of her looked, how many sinful things he wanted to do to her. All of which Noa herself seemed to pick on judging by her brief, moan-laden giggle, her body still pushing back towards him and impaling her onto his cock as best she could, the slick friction of their loins quickly bringing him to his limit.

''Haagh, shit, here it- hn- fuck!''

Until he peaked, slamming into Noa and making her cry out as he creampied her, a torrent of virile heat pouring into her deepest parts. Her legs buckled but he kept her upright, pressing himself into her behind even as he so senselessly nutted in her, pumping her full of baby batter – the consequences be damned. Potent shocks jolted through his nerves and with a groan he pressed himself into her, filling her womb with his seed.

Little by little the intense rush waned from his system and his grip on her breasts loosened, a slow moan working its way out of his throat as he relaxed his hold before letting go altogether, allowing Noa to lay down on the onsen edge and catch her breath. He all but collapsed back into the water, panting hard and with shaking legs but still riding his orgasmic high, though that didn't stop him from gazing up at his naked student.

Least of all when she giggled and turned to face him, breasts pushed up by her biceps and eyes so full of fond affection.

''Let's keep this a secret just between us, hm~?'' Noa whispered playfully.

And with a murmur of his own, he agreed.

Their secret remaining such. For now, at least.

[END]