I have no idea where this came from. Seriously. I'll warn you now, though, that its rating is due to adult themes and sexual situations. It's not especially explicit, but it's there all the same. And if that offends your delicate nature, please feel free to sit this one out. I promise there won't be a quiz later.

Disclaimer: If I owned these characters, I wouldn't be living the life of a poor and starving student.

By day, he belongs to her.

"I promised," he says simply. "I promised her I'd see her every day."

And Sora's not the type to go back on his word.

So there are chaste kisses that glow with childlike innocence. He traces patterns on the inside of her wrist and she giggles. He whispers sweet nothings that tickle at her ear and she blushes like soft rose petals. He puts his hand on the small of her back and she smiles, because she would never imagine Sora to have an agenda.

Together, they are pure and whole and right like the sunshine. They are the perfect couple - characters written for one another.

But Sora lives a double life. And by night, he comes for Riku.

Sometimes Riku wishes he would just stop. Without Sora, he could move on. Find someone else. Someone unattached and uncomplicated, whose eyes are all for him.

But that's not possible. Sora has wound himself in and around Riku's heart like a vine, and he just won't let go. Not after everything they've been through together.

"Nobody else would understand," he hisses as nimble fingers make short work of Riku's belt buckle. "I do. You need me. Only me and nobody else…"

And Keyblade-calloused hands slide down moonpale skin. Bitten fingernails scrape uneven pink tracks along heated flesh and Riku is marked, scarred, branded. Not-quite-pain makes aquatic eyes hazy as they gaze down on cherry-red lips that hover, ghosting breath across open need. He silently pleads, and Sora somehow hears. And then the games are over and warmth surrounds him and Riku gasps and slams upwards into slippery silk and forbidden sin. A swirl of that warm velvet tongue and he groans, flushed and breathless with rocking hips and curled toes and sweat beading sticky through his silver hair.

Sora chuckles at his power. Riku tastes like salt and earth and dark spices and nothing like Kairi. And it's intoxicating and he swallows greedily until fire floods Riku's veins and his hands clench white-knuckled tight in Sora's mane. Something coils in his abdomen and his eyes flutter closed and his hips thrust forward and that name tears from his lips.

Sometimes Riku forgets to warn him, and Sora chokes and splutters and coughs white pearls across the floor. But usually he copes. And then he wipes his mouth with the back of his hand and smiles like the fiery sun - hot and hungry and devastating - because he knows he has Riku for another day. Nothing and nobody will steal him away while he's under this spell.

Sora doesn't know what he'd do if he lost Riku again.

Riku looked at a girl, once. A pretty blonde friend of Kairi's. It remained unsaid, of course, but she reminded them both of Naminé. Soft-spoken and thoughtful, with a sweet smile and a playful laugh. And Riku mentioned her to Sora. Mentioned the possibility of normality after battles and pain and wounds that might never fully heal. And Sora didn't say a word, just watched and listened with eyes burning like hot chemical flames.

That night was the first time Sora came to Riku's bedroom window.

That night, when Sora reached to inch up Riku's shirt, when Sora's lips found his own, Riku pushed him away. He's proud of himself for that. He knew he shouldn't be there. His hands should have been on acquiescing female flesh. His lips should have been curving over shy, painted femininity. He should have been anywhere else, facing anything but the indigo wildfire in his best friend's eyes and the shadows that could hide the shame from everyone but himself.

But Sora… Sora washed away his resolve with kisses and whispered promises and that damned light, and Riku couldn't – can't – say no because it feels so right.

So wrong so wrong so wrong. He knows it. Tomorrow Sora will kiss Kairi with those tainted lips, and she'll never taste Riku's bitter essence lingering on them. She'll smile and giggle like the sweet, unassuming girl she is, and Riku will hate himself for what he's doing. For hurting her, even if she doesn't realise it. For not having more self control. In his mind he apologises a thousand times over, but the dissolving words will never reach her.

All the regret in the world won't make him stop. He couldn't if he tried. He's a creature of the darkness, now and forever, and the darkness keeps all secrets.