A/N: I hereby apologise for my dirty, dirty mind. Seriously though, this was an idea I toyed with during Restless, and I found the notes on it today and thought it might make a good oneshot. Not my best, a bit all over the place, but hopefully the perviness will make up for that!

Voyeur

When he sees her clothing discarded on the floor, he pays it no mind. She's like that, always has been, she leaves her clothes where she was when she took them off. It's only when he sees a t-shirt that's not his, and that's too big to be hers, that the confusion sets in. When he gets to the top of the stairs and hears her voice, soft moans and sighs and no this can't be what I think it is, he finds himself softening his steps so she won't hear him coming. Their bedroom door is ajar, and he crouches down in the hallway to pick up a pair of red silky panties from the carpet, holds them up level with his face and wonders when she got them, because she's never worn them for him. No, she's never worn them for him, but that doesn't mean she got them recently, does it?

They're still in his hand when he gets closer to the door so he can see in and freezes at the sight of them together, at the sound of the muffled groans that he's used to hearing from her when they make love, when she's close to coming and she grips the bed sheets and bites her lip and breathes his name. She's in his lap, her legs are wrapped around him, and one of his hands is running over her bare back, the other one stroking between her thighs. The first coherent thought that drops into his head is 'I thought you loved me, Xiao', and then his mouth twists into a scowl, because sex and love aren't synonymous, you're not that naive Jin, surely.

Her hair's down, falling in dishevelled waves around her shoulders, she breathes out her pleasure, lets her head fall back, and Hwoarang pulls her forward, kisses her neck, her mouth, his hand moving up to squeeze and stroke her breast while Jin watches silently from the doorway. There's anger and hurt and a thousand other nameless emotions all entangled inside him as he watches them, and a single word repeating over and over, demanding an answer from him why why why why why, and he closes his eyes as Xiaoyu opens hers, unaware of him in the darkness of the hallway.

Why not?

Can he blame her, really?

Can I blame her, really?

His eyes open again, and he can't look at them any more, dropping his gaze to the floor and feeling his throat tighten with horror as he realises what looking at them is doing to him, has been doing to him for the past five minutes as he's watched. A hand wanders down to his zipper, and he's disgusted with himself, disgusted and angry and what the fuck is wrong with you, this is not fucking okay, how can you be turned on right now?

There's a crumpled foil wrapper on the carpet he's staring at, and if he doesn't know anything else about her any more, at least he's still right about her being smart. He's undone the zip now, and the silk panties are cool as he strokes them against his cock, gritting his teeth to keep a groan of pleasure inside and watching them through half closed eyes, matching his rhythm with theirs.

You're disgusting.

Xiaoyu's moans make it better, he can imagine he's the one in there with her, and she's about to come now, he can tell by the change in her breathing, and she's coming because of me, I'm inside her, I'm not this poor pathetic bastard standing out in the hallway jerking himself off while someone else fucks his wife.

"I'm gonna…" Xiaoyu gasps, and Jin watches shudders run though her body, his hand still working on himself as she cries out, falling against Hwoarang, and it's a few moments before she comes back to herself and finds the strength to speak.

"God…"

Hwoarang runs his hands down over her stomach, dipping them between her thighs and making her give an 'mmm' of pleasure, while Jin brings himself closer and closer to orgasm, watching her hips move, Hwoarang's fingers still stroking her slowly. And then... then he raises his head and looks straight at Jin, who's helpless as the climax grips him.

You haven't seen me you can't have seen me this can't be happening.

Jin's eyes widen in shock and mortification as he realises what he's been doing. The silk underwear's soaked with his come. A smile creeps onto Hwoarang's face, and he speeds up the movement of his fingers and makes Xiaoyu moan his name. His eyes drop to where Jin's hand has stilled, and he arches an eyebrow.

Jin is infuriated, humiliated, and turned on as hell as he walks into the bedroom.