Paolo Giordano - The Solitude of Prime Numbers

They went into the girls' bathroom. Mattia hesitated. He was about to say I'm not supposed to be here, but then he let her drag him in. When Alice took him inside a cubicle and locked the door they were so close that his legs started trembling. The space not taken up by the old-style hole-in-the-ground toilet was nothing more than a thin strip of tiles and there was barely room for their four feet. There were pieces of toilet paper scattered on the ground half-stuck to the floor.

Now she's going to kiss me, he thought. And all you have to do is kiss her back. It'll be easy; everyone knows how.

Alice unzipped her shiny jacket and started to undress, just as she had at Viola's house. She untucked her T-shirt and lowered the same pair of jeans halfway down her bottom. She didn't look at Mattia; it was as if she were there on her own.

In place of Saturday evening's white gauze she had a flower tattooed on her skin. Mattia was about to say something, but then fell silent and looked away. Something stirred between his legs and he tried to distract himself. He read some of the graffiti on the wall, without grasping its meaning. He noticed how none of the writing was parallel to the line of tiles. Almost all of it was at the same angle to the edge of the floor and Mattia worked out that it was somewhere between 30 and 45 degrees.

"Take this," said Alice.

She handed him a piece of glass, reflective on one side and black on the other, and as sharp as a dagger. Mattia didn't understand. She lifted his chin, just as she had imagined doing the first time they had met.

"You've got to get rid of it. I can't do it on my own," she said to him.

Mattia looked at the glass shard and then at Alice's right hand, which pointed at the tattoo on her belly.

She anticipated his protest.

"I know you know how to do it," she said. "I never want to see it again. Please, do it for me."

Mattia rolled the shard in his hand and a shiver ran down his arm.

"But-" he said.

"Do it for me," Alice interrupted him, putting a hand to his lips to shut him up and then removing it immediately.

Do it for me, thought Mattia. Those four words stuck in his ear and made him kneel in front of Alice.

His heels touched the wall behind him. He didn't know how to position himself. Uncertain, he touched the skin next to the tattoo, to stretch it better. His face had never been so close to a girl's body. The natural thing to do seemed to be to breathe in deeply, to discover its smell.

He brought the shard close to her flesh. His hand was steady as he made a little cut the size of a fingertip. Alice trembled and let out a cry.

Mattia recoiled and hid the piece of glass behind his back, as if to deny that it had been him.

"I can't do it," he said.

He looked up. Alice wept silently. Her eyes were closed, clenched in an expression of pain.

"But I don't want to see it anymore," she sobbed.

It was clear to him that she had lost her nerve, and he felt relieved. He stood up and wondered if it would be better to leave.

Alice wiped away the drop of blood trickling down her belly. She buttoned up her jeans, while Mattia tried to think of something reassuring to say.

"You'll get used to it. In the end you won't even notice it anymore," he said.

"How is that possible? It will always be there, right before my eyes."

"Exactly," said Mattia. "Which is precisely why you won't see it anymore."

Mattia was right: the days had slipped over her skin like a solvent, one after the other, each removing a very thin layer of pigment from her tattoo, and from both their memories. The outlines, like the circumstances, were still there, black and well delineated, but the colors had merged together until they faded into a dull, uniform tonality, a neutral absence of meaning.

For Alice and Mattia, the high school years were an open wound that had seemed so deep that it could never heal. They had passed through them without breathing, he rejecting the world and she feeling rejected by it, and eventually they had noticed that it didn't make all that much difference. They had formed a defective and asymmetrical friendship, made up of long absences and much silence, a clean and empty space where both could come back to breathe when the walls of their school became too close for them to ignore the feeling of suffocation.

But over time, the wound of adolescence gradually healed. The edges of skin met in imperceptible but continuous movements. The scab peeled off with each fresh abrasion, but then stubbornly reformed, darker and thicker. Finally a new layer of skin, smooth and elastic, had replaced the missing one. The scar slowly turned from red to white, and ended up merging with all the others.

Now they were lying on Alice's bed, their heads at opposite ends, their legs bent unnaturally to avoid any contact between their bodies. Alice thought if she turned around she could make her toes touch Mattia's back but pretend not to notice. But she was sure he would immediately pull away and decided to spare herself that little disappointment.

Neither one of them had suggested putting on some music. Their only plans were to stay there and wait for Sunday afternoon to wear itself out all by itself and it would once again be time to do something necessary, like eating, sleeping, or starting yet another week. The yellow light of September came in through the open window, dragging with it the intermittent rustle of the street.

Alice stood up on the bed, making the mattress ripple very slightly under Mattia's head. She held her clenched fists by her sides and stared at him from above. Her hair fell over her face, concealing her serious expression.

"Stay right there," she said. "Don't move."

She stepped over him and jumped down from the bed, her good leg dragging the other one behind it like something that had been attached to her by mistake. Mattia bent his chin to his chest to follow her movements around the room. He saw her opening a cube-shaped box that sat in the middle of her desk, and which he hadn't noticed until that moment.

Alice turned around with one eye closed and the other hidden behind an old camera. Mattia started to pull himself up.

"Down," she commanded. "I told you not to move."

Click. The Polaroid spat out a thin white tongue and Alice waved it in the air to bring out the color.

"Where did you get that from?" Mattia asked.

"The cellar. It was my father's. He bought it God knows when but never used it."

Mattia sat up on the bed. Alice dropped the photograph on the carpet and snapped another one.

"Come on, stop," he protested. "I look stupid in photographs."

"You always look stupid."

She snapped again.

"I think I want to be a photographer," Alice said. "I've made up my mind."

"What about university?"

Alice shrugged.

"Only my father cares about that," she said. "He can go, then."

"You're going to quit?"

"Maybe."

"You can't just wake up one day, decide you want to be a photographer, and throw away a year's work. It doesn't work like that," said Mattia sharply.

"Oh, right, I forgot you're just like him," Alice said ironically. "You always know what to do. You knew you wanted to be a mathematician when you were five. You're all so boring. Old and boring."

Then she turned toward the window and snapped a picture at random. She dropped it on the carpet as well, near the other two, and stomped on them with both feet, as if she were treading grapes.

Mattia thought about saying something to make amends, but nothing came out. He bent over and slid the first photograph out from under Alice's foot. The outline of his arms, crossed behind his head, was gradually emerging from the white. He wondered what extraordinary reaction was happening on that shiny surface and decided to look it up in the encyclopedia as soon as he got home.