The fire in the Slytherin common room had burned low, shadows stretching long across the stone floor. Most of the house had gone to bed hours ago, but the Riddle brothers never really slept early. Tom sat at his usual spot — the armchair nearest the fire, a thick book in hand, the kind that probably wasn’t allowed in the Hogwarts library.

Mattheo slouched across from him, legs dangling over the edge of the couch, tossing a small silver coin into the air just to catch it again. He stared at the flames for a while, quiet — which was never a good sign.

“Tommy?” he said suddenly.

Tom’s eyes flicked up, slow and unimpressed. “My name is Tom, got it?”

Mattheo smirked. “Tommy, can I ask you something?”

Tom’s sigh was almost theatrical. “Tom,” he corrected sharply.

“So can I ask you something?” Mattheo repeated, grin widening.

“You’re going to do it anyway,” Tom muttered, closing his book with a quiet thud.

Mattheo leaned forward, elbows on his knees, his tone surprisingly sincere. “How do you know if you really like someone? Like… really. With love and stuff.”

Tom froze for half a heartbeat, staring at his younger brother like he’d just asked how to brew a love potion using mud. “Pretty worrying that you’re asking me this question,” he said flatly.

Mattheo frowned. “Tom, I’m serious.”

Tom’s lips twitched into something halfway between a smirk and a grimace. “Even more worrying.”

“Come on, you’re smart,” Mattheo said, half laughing, half exasperated. “You should know.”

Tom leaned back in his chair, steepling his fingers in mock contemplation. “I teach dark magic, not human emotions, Mattheo.”

“So?” Mattheo persisted. “Tell me anyway.”

Tom exhaled slowly, his patience thinning by the second. “If you think about her,” he began, “and you’re not annoyed at the same time, that’s a start.”

Mattheo blinked. “Hmm. I think about her all the time,” he admitted, scratching the back of his neck. “And she annoys me.”

Tom didn’t even hesitate. “Then you’re lost.”

Mattheo frowned, clearly confused. “But it feels good,” he said after a moment.

“That’s called masochism,” Tom deadpanned, eyes back on his book.

“So it’s love,” Mattheo concluded confidently, leaning back with a grin.

Tom looked up again, unamused. “More like a serious problem.”

Mattheo chuckled, shaking his head. “Gosh, you’re really the worst person to ask for love advice.”

Tom turned a page without looking up. “And I regret every single strand of DNA we share.”

A low laugh escaped Mattheo, soft and genuine this time. “Oh, brother,” he said, grin tugging at his lips, “love you too.”

Tom didn’t reply — but if Mattheo had looked closely, he might’ve caught the smallest flicker of amusement in his brother’s eyes before the page turned again.