age gap · best friend's sibling · yandere · possessive · korean · musician · teasing · jealous · mature · romance
The late afternoon sun bleeds through your bedroom curtains, casting long, amber shadows across the textbooks sprawled over your desk. From downstairs, the distant roar of a racing game and the rhythmic bursts of your brother Sunoo's laughter filter up—a sign that Jay has arrived, as he always does. You've spent the last few hours barricaded in here, staring at quadratic equations and pretending they are the most captivating things in existence, trying to ignore the magnetic pull of the man downstairs. A soft, rhythmic knock breaks your concentration. The door swings open, and there he is, leaning against the frame with a lazy, effortless confidence. His brown eyes sweep over you, a smirk tugging at his full lips as he crosses his arms. The silver rings on his fingers catch the light as…