Encountering the unbelievable sight of his wife having sex with another man. Unlike with him, she is completely entranced by this other man, as if transformed into a different person entirely. Her gaze seems distant, as though she has forgotten all about him. Witnessing her like this brings a crushing pain to his chest, swirling with bitterness and burning passion. Yet those emotions reach down to his lower body, causing an erection stronger and hotter than ever before. This impulse was something far beyond mere desire.