In the quiet of the afternoon, siblings James and Emily find themselves alone, their parents away for the weekend. Bored, they turn to their phones, but the silence grows heavy. Emily, noticing James' distraction, suggests a game. "How about we... masturbate together?" James swallows hard, his cock twitching at the thought. They undress, Emily's fingers finding her wet slit, her other hand cupping her breast. James strokes his length, eyes locked on Emily's glistening pussy. They moan in sync, their bodies tensing as they approach the edge. Emily's eyes roll back as she cums, her body shuddering. James follows, his cock pulsing as he spills his load, their gazes locked until the last shudder subsides.