AN: I can't believe I'm updating. I should be revising. I should really be revising.

Interlude: Thirteen Reasons Why

He never thought he'd say this, but there's an unfortunate side-effect to having sex.

He watches it in effect right now. Her blue eyes blink up at him, the haze of drugged pleasure slowly clearing. A frown furrows her smooth white brow.

"Black?" she says, as though disbelieving her senses. Her gaze scans the room. They are lying on James' bed, still breathing heavily and covered in sweat, his bare chest pressing against her breasts as he supports himself over her. He is still lodged inside her.

Her breaths begin to come more shallowly as she panics. "What the –"

Sirius sighs. He has to deal with this every single time. Annoyingly, something about physical lovemaking makes the manufactured love wear off. He rolls away from her warm and welcoming body, leaving a trail of their combined fluids glistening on her thigh, to the two things he makes sure to never be without.

One is his wand. The other is a small glass flask.

Alice sits up in bed, frowning absently. She drags the sheet up to cover her nudity from him. "What on earth – ?"

"Petrificus Totalus," he says briefly. He doesn't like it when she gets like this. The first time they had sex and he didn't know what the side-effect would be, she nearly managed to get all the way to Lily and Dumbledore before he caught up with her and performed the Memory Charm. He hates seeing her beautiful face twist into confusion when she looks at him. It hurts somewhere, deep within his chest.

He unstoppers the flask and cannot resist taking a sniff. To him, Amortentia smells like a combination of her skin, the ancestral Black home in Berkshire, and scent of the Chocolate Frogs he and James consume in large quantities every Hogwarts train journey. Sometimes he thinks that he can catch flashes of the Slytherin common room or the Quidditch pitch.

There is a lot he would give to know what it smells like to her.

Her boyfriend, perhaps. The thought makes his stomach tighten with jealousy. After all, she picked Frank Longbottom of her own free will, and if he were to hex the bastard his cover would be blown. And he couldn't have afforded that.

When it comes to Alice, Sirius has a routine; he's been doing it for over a year now, and he's more or less perfected it. Most of the time he lets her carry on with her own life, probably thinking no more of him than she would of the sky. But then comes a point when he can't take that. When he has to have her, be in her, pretending that they are the only two people in the entire fucking world. So then he slips her the Amortentia somehow – a drop in her pumpkin juice at dinner, a tipple into her breakfast milk – and then she is his. She adores him. Wants him.

Loves him.

It only lasts until he's fucked her in a broom closet or empty classroom somewhere. But it'll tide him over for a while. He'll cast the Obliviate, hating that it is necessary. He doesn't just wipe away the memory of their lovemaking; slowly, carefully, at the end of every tryst, he wipes away a little more of her earlier memories involving him. The ones which tell her that she should hate him. And then he lets her go.

The next time she sees him passing in the corridors, there'll be a little less automatic loathing in her eyes, because he is methodically removing everything which tells Alice McKinnon that she should not be getting involved with Sirius Black.

Soon, he hopes, the Memory Charms and love potion won't even be necessary. There will come a time when the way she looks at him after sex will be exactly the same way as she looked at him before it. They're not quite there yet, but they're getting there, hence why she hasn't immediately lunged to claw his eyes out.

He turns back to her prone body. Her mouth is a little open, and he tips some of the Amortentia down her throat. Here at the Manor there's no need to set her free to go her own way. He's decided to keep her under the love potion all the time instead, until such as time as he will no longer need it.

Sirius lifts the Body-Bind. Alice swallows reflexively, and the frozen confusion on her face gives way to relaxed affection. Smiling, he gets back into bed beside her, curving his body protectively around hers.

She rubs lightly at the gash James made on his arm. When she's under the Amortentia, she has a strange fascination with his blood – he thinks that his own initial bewilderment over being attracted to a half-blood of all creatures must have somehow transferred into the potion he brews, until the sight of what runs through his pure Black veins serves almost as an aphrodisiac. He's not complaining. He lowers his head to brush his lips over hers, but there is a sudden abrupt pain in his forearm, and he groans.

"What is it?" she whispers.

"I need to go," he mutters back. "Stay here, love."

He roots on the floor for his discarded clothing and takes a moment to admire her before he goes. She looks so beautiful, naked and slightly flushed, grinning shyly in his – no, James's – bed. Sirius smirks a little. His best friend won't be happy. But then, he's been in a right awful mood since he left Hogwarts. Is it over the fact that the Order of the Phoenix have lately given him a deadline?

It's amusing, it really is, the way James thinks he can keep secrets from his blood-brother. Sirius knows all. He knows that James has been painstakingly teaching himself Occlumency, thus protecting himself against both Legilimency and Veritaserum. He knows that James spent fourth year fucking his girlfriends. He knows that James has a soft spot for Regulus, and that he thinks Cousin Lily is not terrible-looking. He knows that James had to hex Marcus Avery so he could make the Quidditch team in third year, because Sirius was having an off day that day.

See? He comforts himself with this. There's nothing I don't know.

He goes down to see what the Dark Lord wants.

~#~#

Yaxley ignores the burning of the Dark Mark. He will answer the summons soon, but this opportunity is far too golden to pass up. He watches Sirius Black exit James Potter's room.

Then he enters it.

Black's present from the Dark Lord is lounging on the bed, eyes heavy-lidded. She looks up with strangely indifferent curiosity as he enters. He notes that she is not particularly attractive, at least not for someone of Black's calibre, and is amused. Oh, how the mighty have fallen.

He realises that there is something wrong with her. She is under a sheet, most probably fully nude, but makes no effort to cover herself up as he approaches. She might be under Black's protection, but is she not even the slightest bit wary of the fact that an unknown Death Eater is coming closer to her unprotected body?

She probably doesn't have much self-preservation. She's a half-blood faffing about with a Black in the middle of the Dark Lord's headquarters – one can't get much stupider than that. But still, he can't even see that she's got her wand on her…

He stops by the bed, and she finally speaks.

"Are you looking for Sirius? He's gone downstairs."

He sees how dilated her pupils are, the dreamy singsong quality of her voice. Suspicion dawns. Perhaps she's not stupid. Perhaps she's just –

The Dark Marks suddenly flares with even greater agony. The Dark Lord does not like waiting. Mind churning with his theory, Yaxley turns to leave, but suddenly remembers something. He can't have her telling Black about his little visit.

"Obliviate!"

She collapses. He stares – unless you're of very weak constitution, or you've had the Memory Charm cast on you numerous times in succession, people don't normally collapse from it – but there's no time to gawk at it. He needs to go.

But he'll be back, with the things he needs to test this little theory. If what he thinks is true, he won't need to cast the Cruciatus Curse on Alice McKinnon. No, he'll be able to torture Sirius Black without lifting his wand at all.

AN: Okay, so how many of you guessed that?