IncestTRD possessiveness Rarity

>Be Anonymous, and you really want to fuck your sister.
>Like, this goes beyond just fucking to satiate your lust.
>It's like both your heart AND your dick want to do her.
>Every time you watch her work hard on her fashion stuff, or be a good big sister to Sweetie Belle, you get this urge to just pounce her.
>Is it the hormones? Or something else?
>You know every guy in school has their eye on Rarity, and you completely understand why.
>Those not too large breasts...
>That healthy amount of tone.
>Those hips and supple ass...
>She's a goddamn 10/10
>Which is why you feel annoyed when they bring her up in their ratings of the girls in school constantly.
>Which IS why, right now, when it's just the two of you home, you decided to just lay it all out; if there's one thing that's clear is that no one, and you mean NO ONE is good enough for your sister.
>There's a loud thud as you slam your hands against the wall, trapping the slightly shorter Rarity against it.
>"A-Anonymous? What is the meaning of this?"
"Today at school... the hell was that with Noteworthy?"
>"I beg your pardon?" She glares at you.
>You press on.
"I saw him putting the moves on you."
>You grit your teeth.
"And you didn't shoot him down."
>Rarity scoffs and crosses her arms. "It was just a bout of harmless flattery, however I do not understand why it matters to you who I choose to converse with."
>You say nothing for a moment, simply taking in the features of her beautiful face.
"It... irks me. I get this bitter feeling in the pit of my stomach when I see you laugh around guys."
>"Hmph, is my happiness something so vile to you Anonymous?"
"No, I just want you to laugh like that with me... and only me."
>"A-Anonymous!?"

>You run a finger lightly over her blouse.
"Call it jealousy, call it possessiveness..."
>"Anonymous, s-stop." Rarity stands stock still, not meeting your gaze any longer. "I'm your sister..."
"And it tears me up that you are."
>You cup her lithe chin and make her face you as you force her to meet your gaze.
"Call me sick, say that I'm mad, I don't care, when I look at you... I just want to make you mine, the thought of you with anyone else is revolting beyond words..."
>You draw closer, but she faces away, a hand now on your chest.
>"Please, Anonymous... don't do this to me... let me go..."
>You chuckle, though because of your arousal, it comes out a little too throaty and deep.
"Rarity, I'm not holding you or anything."
>You gesture to the open space to her left that she could just walk away through.
"You can walk away."
>"B-But..."
"But what? You think I'm gonna throw a fit? You think I'm going to harm you if you refuse me?"
>She remains quiet.
"As much as I don't want to see you that way, you're still my sister, I'd never hurt you, even if you broke my heart. So go ahead if you want, I won't stop you."
>You watch her intently as she glances between the opening and your feet.
>For a moment your heart stops, the possibility that she'll actually walk becoming a high possibility.
>But despite her awkward shuffling in place, she doesn't move.
>You smile.
"I'm happy, I really am."
>You run your hand through her face, she recoils slightly, but not completely.
>"A disgusting beast like you... if I... If I don't do this then Sweetie might be in danger."
>Your face scrunches up in disgust.
>Also hurt.
"I'd never, the hell do you take me for!? It's you and only you that does this to me."
>With your hand back to cupping her chin, you close the gap and press your lips to hers.
>The kiss, even though carrying your feelings, is awkward at first.
>Partially because Rarity does nothing besides hug the wall with her back.
>At least momentarily.

>As you were about to call it quits, she finally shows some life by leaning into it.
>It makes your heart soar.
>Soon enough, she parts her lips slightly, allowing you to deepen the kiss.
>Between the kissing she pulls back often to say a few words through teary eyes.
>"W-We can't."
>"Ahn~, please, stop this."
>"This is wrong."
>However despite her words, her body presses closer against yours, as she wraps her arms around the back of your neck.
>As if those words were for trying to convince herself rather than dissuade you.
>By the two minute mark, you have moved down from her lips to the nape of her inviting neck, her perfumed scent filling your nose as you do.
>"A-Anonymous please, that might leave a mark..."
>That's exactly the idea.
>Rarity is yours now, and you hers, while nobody would know it, you still want to make a point to the world that she's taken.
>You give her a playful nibble causing her to let out a short high pitched moan.
>You smile as you feel her arm move to her mouth, no doubt she did not expect herself to make such sound.
>You finally break apart from your, now slightly shaky and disheveled, sister.
>Her cheeks are a burning red color that no amount of makeup could hope to match, her eyes having a hard time meeting yours.
"I love you."
>"You idiot, you brute... You foolish... dog. I should report you to the authorities..."
>She says this, yet does nothing to run away, or to show the displeasure to match her words.
>You smile and brush away one of her stray tears, an action you notice she doesn't resist.
>You have no clue how this will go from here on out, but as long as you have Rarity, you feel like this can work.

...

>Alternate End
>You shake your sister to get her attention, she's daydreaming.
>She stirs and comes back to reality.
>"Anonymous?" Her cheeks flush "Do you need something, darling?"
"Geez Rarity, really? I've been calling you for five minutes, I'm going to go ahead and pick up Sweetie Belle from practice now, okay?"
>"O-Oh, of course, come back soon."
>You stare at your sister for a moment, she keeps avoiding your gaze.
"Everything alright?"
>"Yes, yes, of course, just something on my mind, don't dwell on it, on the way home, could you bring back a light snack?"
"Okay. Sure"
>"Thank you."