My God, I am pathetic. Potter caught me with my pants down, literally. I can't even claim I didn't know he was dangerous and treacherous: since he arrived here he has done nothing but try and deceive me; he hasn't thought of anything but escape.

Now he threatens me with my own wand. He is still naked and my cock is exposed, my hand covered in semen.

I am not only pathetic, but also absolutely ludicrous. I have invented an Extended Protego to shield me against non-magical attacks - thanks to it, I was shielded when Potter attacked me with a drawer. But now the little fiend made me lose my concentration. Kill me, Potter. I deserve it.

The boy's hand trembles and my brain seems to start to work again. "You might want to kill me, but I wouldn't do it, if I were you. I have knowledge of things that are of great importance to you, and that no one else can tell you."

"Then spit it out," he says.

I would laugh hysterically, if it were not for my remarkable self-control. "This is not how this game is played."

"Then tell me how it is."

"Very well. You have my wand, so you are the one in control. But let me have, at least, a modicum of dignity. May I go to your bathroom?"

He sighs. "Yeah. But don't try and do anything funny."

Like a plain Muggle, I cleanse the residues of my pitiful solitary pleasure with toilet paper and water. Then I wash my face, avoiding looking at myself in the mirror. I have never hated myself so much in my life.

(This is an overstatement, of course. I should be used to the feeling by now.)

May Salazar help me, I have to be cunning. My life is at stake. Potter has my wand; he calls the shots. I must save my life, but also his. Damn brat.

A clap of thunder rumbles outside in the distance; the weather here changes fast, and it seems a storm is coming.

I come back to Potter's bedroom; Potter is already dressed and sitting on his bed.

"Wouldn't you like to have dinner?" I suggest.

"Only if I can have dinner in the dining room. I'll go after you, and you'll prepare everything."

Hmph. This is a first; now I am Harry Potter's house-elf. "As you wish, Master," I reply, dropping into an exaggerated bow and walking towards the staircase.

We are at the dining room table. The light of the candles flickers; outside, the sound of thunder, the drumming of the rain on the leaves and the fury of lightning compose the scenery. The chicken curry was acceptable, and the wine - a Baron De Lantier Cabernet Sauvignon from 1991, made in Garibaldi, a city in the south of Brazil - superb. Potter looks at me impatiently. I serve the dessert, a very seductive peach pie.

"Snape. Tell me the bloody story."

"Very well, Mr Potter. I know the location of all the four Horcruxes you are looking for."

My statement has the desired effect: he widens his eyes.

"Did Voldemort tell you that?"

I don't even try and conceal my proud smile. "He did."

"I don't believe you. You're making this up so that I don't kill you."

Smart boy. He should have been put in Slytherin. "It was not because of my beautiful eyes that he told me, but because he needed my help. He found out his Horcruxes were under threat."

First he snorts, and then looks at me, bewildered. "How did he find this out?"

"Dumbledore wasn't exactly secretive about the ring, was he? He paraded it everywhere."

"Why did Dumbledore do that?"

"Perhaps because he wanted to provoke what happened. Perhaps he wanted us to be here and now."

"Well, where are the Horcruxes?"

"So impatient." I smirk. "First we have to make a deal."

"I don't want to make a deal with you. Tell me your story or I'll..." He points his wand at me.

"Avada Kedavra," I say, in a poisonous tone, and he shudders.

"Yeah, but I have your wand," he replies, apparently reassuring himself.

"You have my wand, but I have your answers. I offer you a deal: I tell you the location of one of the Horcruxes tonight, and tomorrow you go and destroy it. Tomorrow night I shall tell you the location of another Horcrux, and the next day you shall get rid of it. And so on, until the fourth and last Horcrux is destroyed."

"Very smart, Snape. You're buying four more days of life. But who's going to guarantee me that you won't call your Dark Lord when I go out in search of the first Horcrux tomorrow?"

"We can make a Reciprocal Unbreakable Vow, without a Bonder. The principle at work is similar, but there is no third party arbiter: you will have to trust me, and I shall have to trust you. You vow to come back here every night until all the Horcruxes have been destroyed, and not to reveal to anyone where you are living; I vow to tell you the whole truth about the Horcruxes and not to warn the Dark Lord you are destroying them."

"The one who breaks the Vow will die?"

"Precisely."

He shivers visibly. I would shiver too, if I had any good sense left. There is so much at stake.

"I shall fetch your wand, so that we can exchange wands and make the Vow. We both shall kneel and join our right hands. We shall hold our wands with our left hands and touch our clasped hands with them. I can also vow to give you back my wand after I reveal the location of the final Horcrux. Then you can kill me, if you so desire," I add.

"I agree," he says.

A perfect Gryffindor, as I thought.

We join our hands and make the Reciprocal Unbreakable Vow. It's a solemn moment. Who would have said that one day I would kneel before Harry Potter? Naturally, he is on his knees too, so my pride is intact. Besides, I am doing this for a good cause, and I have drunk too much wine. The latter fact probably explains why I am now looking at him intently and inviting him to go to bed with me. "I have a long story to tell you, and we will be more comfortable on the spacious bed in my double bedroom."

"All right," he says. I would be very surprised, if I didn't know he also had drunk too much wine.

He sits beside me on my bed while I pull a blanket over my body. He takes off his shoes and leans his head on the headboard. He refuses, however, to let go of his wand, ignoring my protests that I have already put mine on the bedside table, that we have made a Reciprocal Unbreakable Vow and that he should feel safe. I begin to tell him the marvellous and very short story of the Hufflepuff cup the Dark Lord stole from Hepzibah Smith. To sum up, the precious cup was entrusted to the care of Bellatrix Lestrange, who hid it in a crypt beneath the graveyard in Little Hangleton where the Dark Lord had been revived. An annoying detail is that the crypt is zealously protected by a Manticore.

He stares at me, bewildered. "And you expect me to go there and kill a Manticore tomorrow?"

"Aren't you 'The Chosen One'?" He looks so dismayed that I take pity on him. I blame the wine for the sudden impulse to cheer him up. "Ask for Hagrid's help. He adores monsters and knows how to tame them. However... there is another detail."

"Another one?"

"You didn't expect the Dark Lord not to protect his Horcruxes, did you? The detail is that Bellatrix cast a protection curse on the cup so that no one would be able to touch it. But, curiously, due to the inner magic of the object, this curse doesn't affect the descendants of Helga Hufflepuff."

"How do you know that?"

"This is a property shared by all the founders' relics," I explain. "The descendants of the founders are immune to curses cast upon their relics."

"Oh... And what do you suggest I do? I don't know any descendant of Hufflepuff."

"Maybe your friend Zacharias Smith can help you. I heard he is descended from Helga and Hepzibah."

"He's not my friend! He hates me!"

"Which proves he has a good taste."

So much for my efforts to cheer him up. Potter glares daggers at me. I pretend not to notice.

"How can I find Zacharias?" he asks

"Do you have Apparition Licence?"

"Yeah. I took it as soon as I became of age."

"I suppose Arthur Weasley can help you to find Smith; he has many contacts in the Ministry. But don't forget your Vow: you cannot tell anyone where you are."

"All right. But I don't know how to remove the Horcrux spell!" he protests.

"You had no great difficulty destroying the Diary."

"Oh, yeah, I just had to defeat a Basilisk. Piece of cake."

"Exactly." I stare at him; he doesn't seem very pleased. "I doubt you would want to be in my place. What do you think it will happen if the Dark Lord comes to see you and doesn't find you?"

He winces. "Can he come here? Did he order you to watch me? Is he paying for the house, the food and everything?"

"Yes, yes and yes."

I am not exactly lying. It's true that he can come here, but it's also true that I know he won't. The Dark Lord is afraid of meeting The Chosen One now that he knows his Horcruxes are in danger.

Potter shakes his head. "Either you're up to something or you're completely nuts."

Both, I suppose. I know I am taking great risks. But he doesn't need to know that. "I won't be talked to in such an insulting way."

"Right," he snarls. "But why are we here? By the way, where are we?"

"We are in Brazil. Why shouldn't we be? It's far from Britain, no one disturbs us and the weather is pleasant, at least in the winter. There are too many crane flies, I admit, but I cast an invisible insect repellent web over the house, so they don't bother us."

"Brazil. It's where the villains go to hide, in the films."

"Really? They are smart, those villains." I yawn. "Now put down your wand, lie down and get some sleep."

I'm pleased to see him obeying and lying down beside me. I feel his warmth, smell his scent of honey, earth and cinnamon soap, and remember his taste when he came into my mouth. I long to touch and devour him, but I have already played the fool today, and I cannot afford to run the same risk again.