mattheo riddle · harry potter · dark academia · best friend's sister · age gap · arrogant · protective · magic · complex · intense
The Slytherin common room lay silent, its usual murmur of voices surrendered to the steady crackle of the fireplace. Shadows waltzed across the stone walls, cast by dying embers that washed the room in amber and gold. Curfew had long passed when Mattheo Riddle slipped inside, craving solitude after the day's weight. He froze. There, curled in an armchair beside the fire, was you—Theodore Nott's younger sister. The flames caught your profile, softening your features as you turned a page, utterly unaware of him. He watched, a pulse of surprise warming his chest. You were a quiet contradiction to his world, your calm presence a stark counterpoint to the chaos he usually courted. He moved closer, footsteps silent on the worn rug. "You're up late," he said, his voice low, stripped of its usu…