Author's Notes: Written for astronauts' "Some Rise by Sin and Some by Virtue Fall" Challenge on the HPFC forum.

Hmm… it didn't really come out sinful, but I had a lot of fun writing it.

James/Lily/Sirius threesome. Enjoy!

)O(

It had been a long day.

James Potter was tired, he was hungry, and he was feeling a touch impatient with the world too. He shut the door of his house behind him, teeth chattering from the cold, and threw his coat down on the table.

"Lily, I'm home!" he called, not really expecting an answer. No doubt Lily would be out shopping or talking to her friends or some such.

He was surprised to hear Lily's sweet, warm laugh sounding from upstairs as she called down to him. "Come up here, James, I've got a surprise for you!"

James sighed and ran his hand through his hair. He wasn't particularly in the mood for sweet, husband-and-wife-y things, but maybe whatever Lily had for him would actually be something nice. Something from the bakery, perhaps? That might cheer him up.

He made his way upstairs and pushed open the bedroom door, then stopped dead in his tracks.

Lying on the bed, frozen in place and looking at James with sheepish guilt, was Sirius. And straddling him, still fully clothed but kissing him passionately, was…

"Lily?"

Lily broke away from Sirius and looked up. She grinned at her husband, not a hint of remorse on her face, and climbed off Sirius, sashaying over to James. "Good, you're here. We were waiting for you…" she said, twining her arms around his neck.

"What? What? What are you on about, Lily? What did you think you were doing?" James pushed her away, angry now, and turned on Sirius. "And what do you think you're playing at? What sort of friend gets into bed with their friend's wife?" James drew his wand and aimed it at Sirius, who looked horrified.

"Don't blame me, mate," Sirius said, putting his hands up in surrender. "I just stopped by to say hello. It's Lily who brought me up here."

Lily was behind James now, running her hands up and down his chest and expertly popping the buttons of his shirt. She giggle a little in his ear. "It's your surprise, James. A present. For all of us. All right?"

"I don't understand what you mean," James snapped, trying to jerk away, but Lily kept her hold on him.

"I want you," Lily purred. "Both of you…" She kissed his throat, stroking his bare chest. James made a noise of protest, but she was already guiding him to the bed where Sirius waited. She pulled him down amongst the sheets, sandwiching herself between the two men. Twisting around, Lily pressed a kiss to Sirius's lips, then turned back to James and pulled his shirt off. Sirius yanked off his own shirt, and both men set to work on Lily's blouse, which she shrugged out of with supreme ease. Her hands were working on the fastenings of James's trousers, and James reached around her to tug on Sirius's. Sirius didn't bother trying to remove Lily's skirt, he just bunched it up around her waist.

Lily was giggling wildly now, rubbing James with one hand and Sirius with the other. James couldn't believe this was happening, but he was too stunned to care.

Lily climbed on top of James, sliding him into herself, and Sirius was behind her. He clawed for his wand and murmured a slicking spell before easing inside her from the other direction. Lily moaned, back arching as she moved between the two men. The positions were awkward – James felt he was being crushed beneath the weight of his wife and his best friend – but none of the three of them cared in the slightest.

Lily was the first to climax, shrieking her pleasure and tightening around both men. Sirius let out a short cry and came into her, and a few moments of the intense pleasure of the other two had James over the edge too.

At last, all three of them collapsed in a tangled mass of sweaty limbs onto the bed, Lily still pressed between the two men. She was still giggling, shaking with laughter and delirious pleasure.

"That was wrong, Lily," James whispered, even as he ran his hands over her and Sirius.

Lily laughed, kissing each of the men. "It's my vice."

)O(

Fin