**Chapter 1: The Unspoken Line**

Kim Chaewon's eyes wandered across the crowded cafeteria, his gaze drifting from one group of rowdy students to another. He had always been the quiet type, content to observe rather than participate. But as he scanned the room, his eyes inevitably landed on one person - Kim Minju. She was the school's most famous girl, and for good reason. Her stunning looks, charming smile, and effortless charm had won over the hearts of many. Chaewon and Minju had been best friends since they were kids, bonding over their shared love of music and video games. As they grew older, their friendship deepened, but it was never romantic. At least, not on Chaewon's part. He had always been content to be her confidant, her partner in crime, and her rock. But things changed a year ago. Chaewon remembered it like it was yesterday. They had been studying for a crucial exam, and Minju had come over to his place, frazzled and stressed. He had made her a cup of tea, and they had sat on the couch, talking and laughing together. At some point, Minju had leaned in close, and Chaewon had... well, he hadn't pulled away. Instead, they had shared a soft, gentle kiss. It was a one-time thing, or so Chaewon had thought. But over the past year, they had sporadically crossed the line of best friends, sharing moments of passion and intimacy. It was a strange, undefined relationship - more than friends, but less than lovers. They didn't talk about it, didn't label it, but it was there, simmering just beneath the surface. As Chaewon watched Minju laugh with her friends, he felt a pang of... something. He wasn't sure what it was, but it was a mix of emotions he couldn't quite untangle. He had always been comfortable with their arrangement, but lately, he'd started to wonder if there was more to it. Minju caught his eye, and smiled, beckoning him over to join her group. Chaewon hesitated for a moment, then got up and made his way over. As he approached, Minju's friends parted, making room for him. "Hey, Chaewon!" Minju said, her voice bright and cheerful. "What's up?" Chaewon shrugged, taking a seat beside her. "Not much. Just enjoying the chaos." Minju chuckled, nudging him playfully. "You're such a wallflower, Chaewon." Chaewon's eyes met Minju's, and for a moment, they just looked at each other. It was a fleeting moment, but it felt... charged. What happens next?