Knocken's heart races as he steps onto the crowded train, his mind filled with illicit thoughts. He spots an empty seat by the window, his eyes locked onto the reflection of a commuter watching him intently. Knocken's hand slides into his pants, pulling out his stiff cock. He starts to stroke, his rhythm matching the train's movement. The risk of being caught only heightens his arousal. He feels the commuter's gaze on him, intensifying his pleasure. His grip tightens, his strokes faster, until he can't hold back any longer. He cums, his load splattering onto the window, leaving a sticky, visible mark for all to see.