The tension had been building for days.
Since the moment Sebastian had heard the words—Isabelle is officially with Marcus—something had settled in his chest, a slow-burning fire that refused to die out. It was in the way his jaw clenched whenever he saw them together. In the way his fists curled against his sides when he caught the easy way Marcus touched her—a hand at the small of her back, fingers brushing against hers.
He had kept his mouth shut. Forced himself to act like it didn’t matter.
But it did.
And when he found her alone in the library that evening, something in him snapped.
“Marcus, huh?”
The words cut through the quiet like a blade.
Isabelle stiffened at the sound of his voice, her fingers tightening slightly around the book she’d been pretending to read. She took a sl
