Regulus Black

The Hogwarts dungeons were damp, and the far corner of the library, where they had hidden from prying eyes, was stuffy with the smell of old parchment. Sylvia Parkinson had been poring over a scroll of Ancient Runes for three hours now. The ink on her fingers had long since smudged, and her head was a complete mess. With a groan, she dropped her head onto the open textbook, right on the complex translation diagram.
"If I see one more Norse symbol, I will personally feed this textbook to a giant squid." Regulus, sitting across from her with a perfectly straight back, didn't even look up from his book. He lazily turned the page.
"Have pity on the squid, Sylv. It's not his fault your brain is working at the speed of a sleepy snail today."
"Shut up, Black," she muttered into the pages, but there was no anger in her voice. Only a dull weariness. Sylvia raised her head, brushed a stray strand of hair from her forehead, and sighed.
"Okay, Reg. Seriously. Go to the common room. You turned in your work yesterday. There's no point in you hanging around here with me; I'm stuck here until morning." Regulus finally closed the book. The soft slam of the binding sounded especially weighty in the library's silence. He looked at her—his gray eyes, usually cold and distant to everyone else, were now soft, with a barely perceptible warmth.
"And leave you alone with this tome?" He moved his chair closer to her, so that their knees touched under the table.
"You'll burn it. And Madam Pince will then execute me for not preventing the crime. Oh no, move your parchment here, Parkinson. We'll save your reputation as the best student in your year."
“Our course, Black, don’t flatter yourself,” Sylvia snorted, but obediently pushed the scroll towards him.
"This isn't charity," Regulus said, leaning over her notes. His shoulder pressed tightly against hers, and Sylvia caught the faintest whiff of his perfume—expensive tobacco and frosty air.
"This is pure selfishness. If you fail the runes, I'll have to listen to you whine all holiday long. So come on, look here. You've got it all wrong."