I've seen people argue he's a minor twist, but honestly, his presence completely re-contextualizes the class from the get-go. He's living proof of how broken Hope's Peak's system was before the killing game even started. They never actually found the real 'Ultimate' they were looking for, and this random dude just walked in. That initial deception—knowing someone is pretending, but not who—casts a shadow over every interaction in the first chapter. It's not just about the one murder later; it's about the fundamental instability of the group's identity. The fact he mostly uses Byakuya's persona means his own impact is quiet, but the reveal that he was the first victim, not the real Togami, scrambles the player's understanding of that entire first case. It makes you question what other foundational truths might be fabrications.
His sacrifice for Fuyuhiko later is also under-discussed. That moment where he sheds the impostor act completely to save someone else, knowing it will almost certainly get him killed, is the purest form of selfless 'hope' in the whole mess. He died as himself, not as a copy. In a series obsessed with talent, his ultimate act was a choice, not a gifted skill. That lingers in the narrative more than any single plot point he engineered.