Sister Lily’s Secret (Black Lagoon)

Sister Lily’s Secret (Black Lagoon)

A/N: Sister Lily's Secret was a commissioned one shot originally written back in July of 2021. Posting it up here and now for people to enjoy!

Summary: In which Sister Lily has a big, dark secret and Asta, no matter how his heart longs for the nun, never ever had a chance.

Themes: Interracial Sex, Quasi-NTR, Anal Sex

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"Sister Lily, please marry me!"

Giggling, Sister Lily Aquaria hides her smile behind one hand as she titters at Asta's heartfelt request. The little boy has been pining after her for much of his short life, and this isn't the first time he's asked her to marry him. Alas, just like all the other times, the beautiful blue-eyed nun can only shake her head in the negative.

"I'm sorry, Asta, but you know I can't do that."

"Why not? I love you with all my heart, Sister! Please, accept my confession and proposal, j-just this once!"

Seeing as he's getting a little too close and invading her personal space, Sister Lily frowns and with a swift hand gesture, positively douses him in ice cold water magic. Yelping, Asta leaps back as she sighs and shakes her head at him.

"Calm your raging libido, Asta. You are in a House of God, after all."

Grumbling, the boy still doesn't look all that convinced. Probably because, no matter how many times he tries to propose to her, Sister Lily always forgives him. As one of Asta's primary caregivers at Hage Orphanage, Lily couldn't help but care deeply for the little boy. She was usually quite supportive of him and his goals... but she couldn't abide by his desire to make her his woman.

Not just because she was a nun, but also because...

"Sister Lily..."

Blinking, Lily glances over as the Father walks up beside her, completely ignoring Asta.

"Yes?"

"You've been requested by name for a Confessional."

Her back straightens and though she does her best to hide it, Lily's cheeks pink up a little as she swallows.

"I-I see. Of course, I'll be right there."

Nodding his head in acknowledgment, the Father continues on his way, message delivered. Meanwhile, Asta is pouting and crossing his arms over his small chest, like the young boy he still is, in truth. Still, he doesn't actually seem to suspect anything is amiss, even as he scowls furiously.

"I know you have lessons today, Asta. Please do not skip out on them again. This is where we must part ways."

None too happy about that, the boy still has no way of stopping her. Giving him one more fond look, seeing him as more like a son or little brother then in the light he wants her to view him in, Sister Lily heads on her way, the blue-eyed nun hurrying towards the Confessional booth on the far side of the building.

Hesitating for only a moment, nibbling at her lower lip nervously, Sister Lily eventually slips into her side of the Confessional and sits down upon the cushion there. She can practically feel his presence from here, the man on the other side of the Confessional's screen.

"Forgive me sister, for I have sinned."

The voice on the other side of the screen doesn't sound very penitent. In fact, that deep, dark, chocolate voice sounds almost amused as he speaks, sending a tremor of a thrill down Sister Lily's back, her legs pressing tightly together and her teeth biting down harder on her lower lip as she fiddles nervously with her hands in her lap.

"O-Oh? What... w-what sort of sins have you committed?"

"Well, you see, Sister, I've been fucking this woman out of wedlock. And I have no intention of marrying her either."

"Is... is that so?"

"Yeah, it is."

His matter-of-fact tone, his amused voice... Lily's hand slips down between her legs, the heel of her palm rubbing against her crotch through her nun's habit as she shivers and shudders, breathing out deeply.

"So, you just... you just use this woman, d-do you? For your own carnal desires?"

"Yeah, I do. She likes it, the silly slut. But still, it's not exactly kosher now, is it? And worst of all, Sister... she's a woman of God too."

Biting her lower lip nearly hard enough to draw blood, it takes Lily a moment to get herself under control. Her hand still grinding into her sex, the trembling nun's voice is shakier than even before when she responds.

"The next thing that the woman of God I told you about does after she takes my fucking load like the slut she is, is get down on her hands and knees and pray to me. Because she's a bitch in heat who knows who her true Lord and Savior is."

Eyes wide, Sister Lily starts to do exactly that, well past the point of resistance by now. But he stops her with a raised hand and a shake of his head.

"Facing the wrong way, Sister."

Trembling, realizing what he truly means now, the blue-eyed, blue-haired nun nevertheless slowly shimmies around on the cushion, until she's facing away from him. Then, she 'bows' forward, prostrating herself for him right there in the Confessional. With her hands and face down on the far end of the cushion, Lily lifts her ass up into the air... and waits for him to make the next move. When nothing immediately happens, something in the broken nun snaps even further and she quivers in lewd arousal as she pipes up.

"P-Please! Please give it to me! I need it, oh Lord! I need it so bad!"

She doesn't have to wait long after that. No sooner is Lily in position and begging for it, then his large, strong hands are on her backside, kneading her ass cheeks through her habit as the nun moans wantonly in response. He doesn't spend too long molesting her though, instead gripping tightly at her habit and then yanking it up and over her fat ass and wide hips. As her naked, pale bottom, bereft of undergarments, is revealed, he whistles sharply.

"Damn, that's one fine ass..."

"T-Thank you..."

He just laughs at her gratitude, before delivering a stinging slap to her buttocks that makes Lily squeal in response. Then, his big black cock, still all messy from her inability to swallow all of his cum, begins to tease at her gushing wet pussy lips. He's going to deflower her right then and there, isn't he? Sister Lily tenses up, the part of her that was still proud of her service as a nun warring with the belated sexual awakening she's experienced that turned her into a BBC slut.

She can't decide what to do, whether to tell him not to take her virginity, or whether to beg for it. His cock feels so good against her pussy lips, and she wants nothing more than for him to claim her. But if he does, she'll be even more impure than she's already become, she'll-

In the end, her worries are cast aside when he makes the decision for her... and it turns out his intentions are not what she expected at all. Rather than deflower her, it turns out he was using her dripping slit as lubrication... all to make his true target easier to take. In one smooth motion, those big black hands of his spread her ass cheeks apart, and before Lily knows what's going on, she's taking his cock right up her lily-white ass.

Blue eyes go as wide as saucers as he drills into her from behind, and her squeal turns into a shriek that's silenced a moment later by one of his large hands covering her mouth. He chuckles into her ear as he leans over her, taking her anally without an ounce of hesitation, splitting her poor backside upon his massive black cock like it's nothing, like it was to be expected or something.

"Damn girl, you're a fucking screamer, aren't you? Keep quiet. Don't want us to be found out now, do we?"

No... no she did not. Eyes watering, Sister Lily is nevertheless enjoying this, probably more than she should be. His cock is so big, so thick, so long... it feels like it's splitting her ass in two. But at the same time, the whole situation is just so debauched and depraved that the nun can't get enough of it. She truly is a scarlet woman; she truly is a slutty little nun whore for her big black master's big black cock...

Holding her mouth shut, he begins to butt-fuck her right there in the Confessional. Yelps and squeals and moans are all swallowed by his palm as Sister Lily finds herself in a truly humiliating pose, supplicating and prostrating herself on her knees on the cushion as he fucks her from behind with hard, deep thrusts that grow faster and faster the more time goes on.

"Oh yeah, you take it you sexy little nun. Take my fucking cock up that tight ass of yours."

Any pain is swiftly swallowed up by pleasure, proving even further that Lily Aquaria truly is nothing more than a whore at the end of the day. Nothing more than HIS whore, her entire body shaking and trembling under the onslaught of sensation he's forcing upon her. Then, all of the sudden, he speeds up and it's all Lily can do to hold onto her fraying sanity.

WHAP! WHAP! WHAP!

He's pistoning in and out of her ass now, pounding away like there's nothing to it. His hefty balls are swinging up into her gushing cunt and making a slick wet smacking sound as he plows her pale bubble butt silly. Lily, for her part, can't hold it back any longer. She squeals mightily as she cums from the anal plundering, her blue eyes rolling back in her head as her tongue sticks out only to run right into the wall that is his large bear paw of a hand.

He grunts as her anal muscles tighten up around his cock, but it doesn't stop him from continuing to go to town on her, roughly slamming home into her ass and filling her bowels with his dark cock meat again and again and again. In the end, Sister Lily's eyes stay rolled up in her head, and she doesn't stop cumming for the rest of the butt fucking, squirting her pussy juices all over the inside of the Confessional in a truly lewd manner, even as he takes his pleasure from her.

This was why she and Asta could never be. As much as she loved the boy, as much as she cared for him in a familial sense... she knew he could never stand up to a man like this. He could never compare to this big black beast who was fucking her senseless with all his might.

"Shit! Here it comes, you nun slut!"

His hands go down to her hips, and he slams home into her ass one final time as Lily arches her back, her head tilting up and her face one of overwhelmed tears but also euphoric ecstasy. With her tongue hanging out, she looks so fucking stupid, even as he begins to paint her bowels white with his thick, hot seed.

"Y-Yesh! Yesh, fill my asssssss!"

He just chuckles and does as she bids him to, pumping his load right into her ass and then pulling out to deliver the last few spurts of thick, sticky, ropey cum all over her pale buttocks and the small of her back. The explosion of hot sticky fluid inside of her, combined with the complete disregard for her as he marks her as his property... it all proves too much for the beautiful buxom Sister.

With one last shuddering breath, she flops forward, face down and ass up on the Confessional cushion, passing out on the spot from the over-exertion.

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