Chapter Text
Tsukasa was raised into Christianity. He'd always go without a complaint and enjoyed helping and volunteering. Their church was small of course— Christianity is very small in Japan. His peers would always look at him weird whenever Tsukasa would talk about being busy after school because of church but it never discouraged him or his faith.
Because of this Tsukasa never found a partner and decided that this was his God's way of telling him to become a priest. After all, it makes sense due to how devoted the boy is to his church and small community.
Eventually Tsukasa took over and to everyone’s surprise more people became interested in their church because of Tsukasa.
Many say it was because of the way Tsukasa spoke so confidently and passionately about his religion, others were simply captivated by Tsukasa in general. After all Tsukasa is a kind and caring soul who believes everyone will one day go to heaven.
Every night he prays alone once everyone leaves. He finds it easier to be vulnerable to his god when he's alone. Everyone looks up to him so Tsukasa can't bring himself to show any weakness.
Just like tonight, Tsukasa prays. His hands pressed against one another as he speaks aloud— hoping his god will hear him tonight.
“My good Lord, here I am again tonight, hoping for your presence. Today we had more people show up— one of them was a father who was looking into churches nearby and said he was drawn here after hearing about me. Yet I feel as though it was your doing that led him here. I cannot take credit for my good Lord's actions. He told me that he has a sickly child and it reminded me of my little sister… Oh Saki… She hasn't come to church in a while… I can't help but be worried about her. When I asked when she visited me at my house yesterday she said she doesn't have time for worship because she's making it big in the music industry. She worries me a lot… I fear a devil could be clinging to her— especially after moving to the big city and all… I ask of you to watch over her and guide her… Please don't let my dear little sister stray from your glorious light. The thought of us not spending eternity together once it is our time pains me, my Lord.”
Tsukasa always rambles on and on, as if he's talking to a friend instead of his god. There's been nights where Tsukasa doesn't leave until two in the morning.
As Tsukasa talks he hears the door open and slowly close but he pays no mind to it. Sometimes the nuns come through to grab something they forgot so he ignores it. That is until he feels something in the air… shift.
Tsukasa pauses mid sentence and realizes something is off. Immediately Tsukasa discards what he was saying and begins his prayer.
“My father in heaven I pray for your protection, that your holy light will shield me from the darkness and lead me to your divine light. I shall resist all that is evil and sin and follow your path carved out for me. For no demon can lay its fingers on me as I am protected by you at this very moment on this sacred ground blessed by you. I beg of you to ward off the evil spirits that attempt to wander in this sacred place…” As Tsukasa continues he can feel its presence coming closer until without a doubt— a demon stands behind him.
Against Tsukasa’s better judgement his voice trails off as his head turns to look behind him.
He expected to see a monster of sorts, not a man with lavender hair with two oddly placed cyan stripes, piercing yellow eyes, and a feline-like smile. And yet Tsukasa can feel the demonic presence radiating from this man— no, this demon.
The man smirks and tilts his head to the side, dressed in a suit, hands tucked into his pockets. “I will say, it's adorable how humans believe their words can ward off demons… Unfortunately you would've been dead by now had I had the intent of killing you,” the man says with a cocky look in his eyes.
Tsukasa glares up at him. “What gives you the right to think a demon can walk on holy ground?” Tsukasa asks, quickly rising to his feet.
The demon shrugs. “Because I can? Just because you humans deem this as “holy ground” doesn't actually mean it's protected by God. You'd be surprised how little land is actually protected,” he responds.
“Tch… What brings you here then, demon? I know you have no intent to cleanse your soul of sin.”
“Rumor had it that there was a cute little priest who's been getting a bunch of lost souls captivated with his passion for his Lord and savior. I got curious to see if the rumors were true and I will say… They certainly didn't do you justice… You might be the most tempting thing to ever walk this world,” he says, eying Tsukasa up and down.
Tsukasa is taken aback a little, even blushing slightly but quickly recovers from this smooth talking demon. “I have no care for the opinions of others. All I care about is what my Lord thinks of me. Everyone else's opinion is irrelevant,” Tsukasa insists before turning his back and grabbing his stuff off the podium.
“Oh~? Well the Lord most certainly blessed you with quite the ass,” the demon chuckles.
Tsukasa stops, his face burning a bright red before whipping his head around, Bible and cross in hand as he stomps towards the tall demon.
“You shall not bring your sin into my church! Begone!” Tsukasa shouts, shoving his cross into the demon’s pale face.
The demon laughs and ruffles Tsukasa’s blonde hair. “Ahhh… You might be the first human I actually enjoy being around. You're too cute for this world aren't you?”
Tsukasa pouts, his cheeks puffed out.
“Tsukasa, right? Call me Rui…” Rui takes Tsukasa's hand in his and places a kiss on top of his hand, “I must take my leave… But expect me again here tomorrow…”
Tsukasa glares at Rui as he begins to walk away before stomping his foot against the ground. “If you come here tomorrow I'll drown you in holy water! You beast!”
Tsukasa watches Rui simply wave him off and leave, only irritating Tsukasa more.
He sighs and calms himself down, looking to the stained glass of his Lord.
“My Lord… I pray you shield me from that demon above all other ones…”
☆☆☆
From there on out, Tsukasa is visited nightly by Rui.
Sometimes Rui waits patiently for Tsukasa to finish his prayer and other times he bothers Tsukasa so much he can't continue where he left off.
And sometimes on peaceful nights Tsukasa sits by Rui on the stairs that lead up to his podium and they talk. Rui is a very good listener and Tsukasa can't help but feel like Rui enjoys hearing Tsukasa talk about his day. Rui doesn't talk much about himself though— Tsukasa isn't sure why.
All he knows is that Rui is specifically an incubus, not the typical demon Tsukasa originally thought Rui to be. With that in mind it makes sense why Rui wanders the human world like he does. Yet for an incubus who is made to tempt humans to lust, Rui is much better at tempting Tsukasa's heart to love.
It is a sin not just for Tsukasa to lay with another man, but a demon no less as a priest.
And yet Tsukasa can't help but fall in love with Rui. He's sure the demon has caught the way he stares at him and listens to Rui so intently whenever he talks. He knows an incubus wouldn't be blind to something like that.
Had Tsukasa not been a devotee, he surely would've fallen in love with Rui—
Tsukasa is pulled from his thoughts, sitting on the staircase when Rui slams his doors open.
He's only ever seen Rui in his human form, but tonight Tsukasa sees Rui in all he demonic glory. Taller than what he already was, his eyes more of a glow, his horns and tail are now visible, and his feet are that of a beast’s rather than a man's.
“Forgive me for coming like this tonight… I'm a little weak right now…” Rui laughs weakly, limping towards Tsukasa.
Tsukasa rushes over as Rui begins to fall, catching him but struggling to keep Rui up since the man is so heavy in this form.
Rui falls to his knees as Tsukasa tries to keep him up, clinging to Tsukasa desperately.
“What happened? Were you struck by God? Were you attacked by a divine artifact? Did—”
“Hah… Wouldn't that be funny? Tsukasa-kun I… I haven't been quite honest with you about myself. I was worried that I'd scare you off if I told you who I truly was,” Rui admits.
“Then tell me Rui. I won't run or kick you out…” Tsukasa says softly, running his hands along Rui's lavender locks.
“I am not just some incubus… I am the sin of lust itself…”
Tsukasa's eyes widen, freezing as his brain begins to process what Rui just told him.
The sin of lust? Asmodeus himself in the flesh? But what would a sin like Rui be doing by humoring himself with such a lowly priest like Tsukasa?
“To be honest I really wanted to have sex with you… I thought it'd be adorable having a little priest wrapped around my finger but it seems that I'm wrapped completely around your finger. Since we met I found less enjoyment having sex with random humans and even demons. So I stopped having sex altogether because if it wasn't you, I didn't want to have sex. However that's a problem when demons like me rely heavily on sex to survive. Humans eat food to survive, we incubus and succubus feed off a human’s lust and sexual energy during sex. Of course we can go longer than a human without eating but I fear I've reached my breaking point…”
“Rui you… I can't believe that the sin of lust would do that and yet…” Tsukasa tilts Rui's head up, “did you truly stop having sex because of me?”
Rui nods. “The only soul I wish to have sex with is you. I thought love was such a stupid thing that could be easily manipulated and used so I could get what I want from desperate humans… But after falling so hard for you my perspective changed. My love for you chains me to you. Even if you deny me here and now, I still will refuse to have sex with someone even if I die. It's not worth it if I can't have sex with you,” Rui says.
“I don't want you to die Rui… Even if it damns me to hell, even if I'll never be able to spend eternity in peace… I can't help the way I've fallen in love with you. My heart couldn't stand losing you…” Tsukasa admits, tears falling from his eyes.
Rui stands up weakly and rubs the tears from Tsukasa's eyes.
“Tsukasa-kun… I beg of you, please have sex with me… Even if you're casted to hell for all of eternity, I'll make sure not a scratch lands on you,” Rui promises, pulling Tsukasa close.
“I'm probably not very good at sex though… I refused to even learn about it. I didn't want my mind tainted with sin so…” Tsukasa looks away with a nervous smile on his face.
“Is that so? Rest assured, I'll pleasure you tonight and you won't have to lift a finger…” Rui says, placing a kiss on Tsukasa's neck.
“R-Right… Uhm… How do we…”
“Oh my, you truly are completely clueless aren't you?” Rui chuckles and guides Tsukasa to lay down on the church floor. “I don't mind doing all the work for you~ Usually with those that summon me, I make them work for what they want… But you? My dearest priest deserves to be pampered and spoiled in bed…” Rui’s hand trails down Tsukasa's body, his claws tearing at the fabric as he reaches Tsukasa's pants.
Tsukasa feels something forming in his stomach. Is this sexual excitement, perhaps? It's such an odd yet… good feeling…
Rui tugs off Tsukasa's pants only to be met with a pretty pussy— untouched and unclaimed.
Tsukasa watches saliva escape Rui's lips. He huffs and kicks Rui lightly. “Is the sin of lust truly such a pervert?”
“Only for you, my dear~” Rui responds, wiping the saliva away and pulling Tsukasa closer, squeezing the fat on his thighs. “By the gods… I could play with these all night… Press these pretty things against my dick and have you watch me fuck them—” Rui looks up to see Tsukasa completely weirded out and chuckles. “Forgive me, I forgot how vanilla my dear priest must be… Such a thing won't do though, you know? I'll teach you everything about sex…”
Tsukasa rolls his eyes. “You're stalling,”
“It's called foreplay, my dear. It's a necessary part of sex if you ask me…” Rui presses two fingers against Tsukasa’s slightly wet pussy. “You feel that? That wetness beginning to build up? That's good… It means you'll be more willing to open up to me… But even at the height of your arousal you're simply too small for me. So I'll give you something special to assist us during sex,” Rui says.
Tsukasa watches as Rui moves his hand to above his womb and presses down, a glow emanating from his palm.
“W-What are you doing!? Are you placing a marking of the best onto me!?” Tsukasa shouts.
“Sort of… It's my marking,” Rui says.
Tsukasa swallows hard at the way Rui puts an empathise on that. “Y… Yours? Do all sins have different markings?”
“Pft, of course we do. Mines have more variety than say that knuckle head Akito. Or better known as the sin of wrath. He only has one type of marking that he brands onto his demons. Mines are all different and have specific meanings. As for the one I'm giving you…” Rui pulls his hand away. “Only one other demon has this marking, and that's me… That way if any other demon dare lays a finger on you, you'll be protected by me. That lousy god you pray to hasn't offered you anything. If he did I wouldn't have been able to so easily place a marking on you,” Rui explains, his tone more serious… possessive even.
“My womb…” Tsukasa blushes deeply, tracing his finger over the pretty patterns Rui had covered into his skin. In the center lies a heart, scribbles and swirls form into two wings on each side.
“Pretty isn't it? Yours is slightly modified but the power in it is exactly identical to mine. So if you happen to die and I don't notice it until later, you won't be sent to Hell’s eternal torture until I arrive and bring you to my circle of hell,” Rui says with a grin, admiring the marking on Tsukasa's lower region.
“I'll never see heaven’s gates then?”
Tsukasa's question catches Rui off guard.
“I… No… Unfortunately you won't. Your greatest sin was making a friend of a demon and because of that it cursed your soul. No matter how much you prayed and begged for forgiveness I could sense that your eternal Lord has completely given up on you. When I first entered the church I could feel his gaze lingering but after a month of showing up his gaze turned away from you. I never understood the human’s desire to be noticed by a god such as he— so cruel and strict. But you will not be punished because of me, I'll make sure of that,” Rui promises.
Tsukasa is conflicted. He knows he can't go back now. With what Rui told him he'll never be able to appease his Lord anymore.
“I see… Then let's not waste any more time… You must be really hungry, right? Then drown me in your sin, Rui… Show me why so many fall victim to your lust,”
Tsukasa watches excitement bloom in Rui's eyes.
Tsukasa whimpers when Rui's thumbs spread apart his fat pussy lips.
“Ah… That's right, you'll be extra sensitive because of my marking~ You see… If a demon has sex with another that has the same marking as them, then they'll experience pleasure like never before. It's mostly because they're linked. It's a bit complicated to explain to a human— especially one who doesn't even have any knowledge of sex in the first place but you'll figure out what I mean soon enough… For now, I've been dying to get a taste of you…”
Rui lifts Tsukasa up slightly until his mouth meets Tsukasa's cunt.
A loud gasp escapes Tsukasa's lips as Rui's long, rough tongue begins to attack his cunt repeatedly, targeting his hole. It pokes and prods until finally it slips inside, making a loud moan rip out from his throat.
“R-Rui…! It feels so weird but so good…!” Tsukasa cries out, clawing at the wooden tiles on the ground.
Rui hums, holding the priest’s chubby thighs tightly as he eats Tsukasa out.
The slurping noises are so lewd and the groans make that weird feeling in his stomach build up.
Is this what it feels like to fall into lust? I used to scold teens who fell to lust’s— or rather Rui's temptation, yet here I am falling for Rui directly. But I can't even blame them… This feeling is so amazing that I want more and more…
Tears escape Tsukasa's eyes as Rui begins to rub his clit while eating him out so enthusiastically. His tongue digs deeper and deeper, exploring every crevice inside— making sure it's all marked.
Tsukasa's legs twitch, something in his stomach feels like it's about to burst.
“R-Rui! Wait! Wait! S-Something feels weird… My stomach… I think I'm gonna pee…?” Tsukasa whines
Much to Tsukasa’s dismay Rui becomes even more aggressive, his nose buried in Tsukasa's cunt as his tongue moves more frantically.
“A-Ah…! Rui! Rui! Wait I'm gonna—! It's going to—!”
A loud, drawn out moan comes from Tsukasa's lips as he experiences his first ever orgasm, his body twitching at the intense pleasure.
Rui happily licks all of Tsukasa's cum and slick up when a little bit of liquid escapes Tsukasa's cunt.
He's too high up in the clouds to notice, however, only being brought back to his senses when Rui chuckles at it.
“H-Huh…?”
“How cute… All I did was eat you out and your naughty pussy squirted onto me… So precious~” Rui growls.
Tsukasa's face flushes red in embarrassment. “I-I-I did!? I-I’m sorry I didn't mean to pee…! Oh my goodness what an embarrassing thing to do…” Tsukasa whines, covering his face.
“Is adorable~ Besides it's nothing. I've had someone actually piss on my face before so it's not like I care. I wonder if your cute little pussy will piss on my cock after I cum inside though… What an intriguing thought…”
Tsukasa squeaks when Rui licks his lips and quickly shakes his head. “The sin of lust is a massive pervert!” He cries out.
“Only for you~”
Tsukasa kicks Rui’s side roughly. “Shut it! I'll let you starve!”
“Oh don't lead me on like that… If you do, I might have to… steal some from you instead…” Rui gropes one of Tsukasa's thighs roughly, moving him down until he rests right against Rui's bulge. “I would advise not making me do that though~”
“P-Perverted…”
“Mhm~ Is that all you can say?” Rui teases, grinding his bulge against Tsukasa's pussy.
“Ah— ah~! It's ha-hard to think when you do that~!” Tsukasa cries out, slick gushing out of his small hole.
“I'm sure it is~ Our markings are so close after all… You'll probably cum everytime I bottom out inside your cute pussy… Our markings will be so close… Your human body wouldn't be able to handle it…” Rui says, his hand rubbing the marking, making Tsukasa jerk and moan. “Adorable~”
“Stop~~!! M-My pussy—”
“Yeah? It's so needy isn't it? All it needed was a proper marking and I turned this body into a cock hungry slut for my dick… After tonight I'll make sure you're begging me every night for more and more… I'll even fuck you during your prayers… How does that sound?” Rui growls, humping Tsukasa as his cock desperately tries to break free from Rui's pants.
“Pl-Please…! My body wants you Rui…!” Tsukasa begs.
The marking has completely taken Tsukasa over now, making him fully desperate for Rui's dick.
“There it is…”
Rui frees his cock, letting it slap against Tsukasa's wet pussy with a wet “plap!”
Tsukasa stares at the monstrosity before him in a mix of excitement, awe, fear, and dread. It's massive, maybe as big as his thigh— probably bigger. It's thick and so heavy against his tummy. It's drooling with a white liquid all over him, leaking its fluid.
“T-This is a penis…? No way… That's a monster… S-Some sort of satanic beast…”
Rui grins and grinds his cock against Tsukasa's pussy.
“Mhm~ It is a beast, isn't it? It's only fitting that the sin of lust is well endowed after all… But don't worry, this marking will take all that pain and turn it into pleasure. That's the good thing about these naughty womb tattoos, they'll provide the best part about sex and get rid of the troublesome part which is the pain humans feel when I try to enter… It also technically casts a sort of protection to prevent tearing and bleeding of the womb. Under normal circumstances humans would require medical attention after but my magic allows humans to experience sex with me without pain. Amazing isn't it?”
Tsukasa nods nervously. “So I won't die from your dick…?”
“Nope~ Unless you die from pleasure that is~” Rui says, positioning himself so the tip presses against Tsukasa's pussy.
“Mmph…! B-Big…”
“I know~ it's so wonderful isn't it~?”
Tsukasa nods as Rui's tip pushes itself inside. “Ah~! Rui's inside of me…”
“That's right… I'm tainting this body of yours with my sin~” Rui purrs into Tsukasa's ear, pushing more inside.
“Ah…! M-My body is being filled up~!” Tsukasa cries out.
“You'll take it all, right Tsukasa-kun? This slutty pussy wants all of my dick, right?”
Tsukasa nods eagerly. “M-My slutty pussy wants dick…!”
Rui's claws dig into Tsukasa's meaty thighs at the blonde’s whorish words, making Tsukasa moan again.
“Good… Then take it all!”
Tsukasa screams when Rui slams it all the way inside, his marking rubbing against Tsukasa's.
Immediately Tsukasa cums all over Rui's dick, his body twitching as he experiences his second orgasm.
“Haha… How adorable~ You really did cum all over my dick just from our markings touching… Such a fucking slutty body~” Rui growls, licking Tsukasa’s earlobe.
“Ahh…♡ I dunno what it means but yes… I have a slutty body for Rui♡” Tsukasa's moans.
“A slutty bitch is someone who loves dick and sex… Tsukasa-kun loves dick and sex, doesn't he?” Rui asks as he grinds his tip against Tsukasa's cervix.
“Ah~! I do♡! I'm a slutty bitch…♡”
Tsukasa moans when Rui spanks his ass. He clicks his tongue, claws digging into the flesh.
“A priest shouldn't use such sinful language now should he~?”
“N-No…! Forgive me Rui…♡”
Rui pats Tsukasa's head. “Good boy~ I'll always forgive you even if you're being so naughty like how you are right now~ Wouldn't I make a kinder god than that prick who hangs out in the sky?” Rui teases, beginning to move his hips.
“Mhm~! Rui makes me feel so good…♡” Tsukasa moans as Rui thrusts in and out of Tsukasa's pussy.
“If I was your god… All you'd have to do is worship my cock with your naughty little mouth and pussy… And you could do whatever your little heart desired~ As long as it isn't having sex with someone else… If you ever did something like that I'd punish you properly… You're only mine, after all~”
“Yes♡! Only Rui's♡!” Tsukasa says happily as Rui's big dick moves in and out of his slutty hole.
“Heh… Good~”
My womb tattoo affected Tsukasa-kun more than what a normal human should be affected. A lot of factors could play into this— Tsukasa's lack of sexual experience, the fact he's bound to my marking of all the other one's I could've given him, and the fact his cute little mind can't handle such a big dick inside his adorable pussy~ Ah, a human shouldn't be so addicting like this… Maybe I should make Tsukasa turn this boring old church into a place of worship for me~ If I could I'd make sure he'd get creampied during sermons… I'm sure he'd enjoy it anyways~ Rui thinks with a satisfied smirk.
Rui allows himself to become a bit rougher with Tsukasa, picking up the pace as he pounds into the blonde’s cunt.
The lewd, wet noises echo throughout the church, combined with Tsukasa's naughty moans only add to Rui's arousal.
Defiling such a sacred place while destroying this priest’s cute little pussy is such a massive turn on. And the fact it's Tsukasa who he's fucking is making Rui feel pleasure he's never felt before either. He's resisting every single urge to go all out on Tsukasa. He knows he can't today… But one day he's going to snap and won't be able to hold back.
But at least now Tsukasa is tainted by him— claimed by him.
Rui can feel it, Tsukasa's soul is his and his alone… No other sin or demon can steal it away from him. It's all Rui's.
“Ah~ Look at how wet my dick is, Tsukasa-kun~ Did you pee on it already~?” Rui teases.
“Ehh~? Did I pee on Rui's dick…?” Tsukasa moans.
His eyes are glazed over and unfocused, tears streaming down his face. Rui doesn't even think Tsukasa is on the same plane as him right now.
“My naughty priest~ Make a mess all over my dick because you can't control yourself~” Rui chuckles, spanking Tsukasa's ass again.
“Sorry~~! I can't control myself anymore…♡ I just want more~”
“Good… I can give you more~” Rui grips Tsukasa's hips roughly and pulls him up.
Rui sits back and starts fucking Tsukasa roughly on his dick, using him like some sort of onahole. Tsukasa clings to Rui tightly, his nails leaving pathetic scratch marks on his back as Rui's dick absolutely destroys his hole.
“Rui~! Rui~!” Tsukasa screams, his slick soaking Rui's pants.
“That's it! Take it all, Tsukasa-kun~! Your pussy was made for my cock, wasn't it!?”
“Yes~! Yes it was, Rui~!” Tsukasa cries out.
Tsukasa didn't need to be told twice that his fate is sealed in hell. But it doesn't matter anyways— he won't be tortured because Rui said so, so why does Tsukasa care?
Rui will keep giving him this good feeling again and again… Tsukasa's mind will melt over and over as Rui's big dick fills him up and leaves him cumming all over his cock nonstop.
Tsukasa's true eternal paradise is already right here— with Rui♡
Tsukasa screams as Rui's burning hot cum fills his womb, his whole body tensing and mind cutting out as he finally experiences the sensation of his poor, lonely, empty womb being filled to the brim with cum.
Tsukasa twitches slightly as Rui slowly pulls Tsukasa off. Once Rui's cock slips out, a flood of cum escapes, no longer being plugged up.
Rui lays Tsukasa down and moves on top of him, staring down at the now exhausted priest.
“Hah… Ah… Lust is such an amazing sin…" Tsukasa pants heavily, his eyes ever so slightly more focused now.
“Of course it is… Lust gives off such an amazing feeling that other sins just won't give you~”
Tsukasa pants and nods.
“Rui… Are you full…?” Tsukasa asks.
“Hm? Ah, yeah. Tsukasa-kun has me all stuffed~ The sexual energy of a virgin experiencing sex for the first time fills any demon right up~”
“I'm glad… My mind is still trying to come back to me… But that was really good…” Tsukasa pants.
“Heh, you did good, Tsukasa-kun~” Rui praises, patting Tsukasa’s head.
Tsukasa blushes and leans into Rui's touch. “If it's not too much… Is it okay to call you my lover, Rui?”
“Yes,” Rui answers immediately with such a straight face.
Tsukasa smiles softly at Rui. “I’m glad… Now please take me to my home… I'm really exhausted…”
“Mhm~ Of course~”