Professionalism in the isekai genre is not a trait but a defense mechanism against the inherent instability of a new world. While Lugh Tuatha Dé and Seiya Ryūgūin both operate as high-efficiency technicians, their identical growth trajectories mask a fundamental divergence in why they optimize. Lugh treats his second life as a clinical optimization problem, refining mana output and tactical precision to ensure he is no longer a disposable asset. His journey is an attempt to manufacture a soul through the rigid application of logic. In contrast, Seiya’s caution is a response to the systemic failure he experienced in Ixphoria. He does not seek to build a self; he seeks to eliminate the possibility of loss. This distinction manifests in their DNA profiles: Seiya’s Bond score of 100 proves his hyper-vigilance is an act of absolute devotion, whereas Lugh’s lower score reflects a man still learning how to value people over objectives. The shift from YPS-3 to YPS-4 between them is less about raw output and more about the scale of their anxiety. Lugh manages the destiny of a city through unseen hands, but Seiya treats an entire nation as a potential extinction event. The comparison reveals that when a protagonist removes chance from the equation, the resulting power is actually a manifestation of deep-seated fear. Efficiency is the mask they wear to survive a universe they no longer trust.