I would say Teppei was one remarkable NPC whose story affected me the most and left a mark that will remain forever. If you observe carefully, then most characters in the game try to take benefit of the Traveler and make them do the tasks they need to be fulfilled. Rarely does it happens that they get to know anything from the characters in the game, and usually, the Archons avoid all sorts of questions. Dainsleif is one character who is a bit more open about the events that happened in the past and speaks openly about them. But Teppei has a different vibe. I mean, he was one of the most genuine characters in the game who treated the Traveler more than a friend. The guy cared for the Traveler till his last breath and always wished well for them. Scaramouche might not be behind delusions, but I'm going to snap his neck for mocking Teppei's death. I'm pretty sure a lot of people were sad about his death, and I got messages from a lot of people that they were sad about a character's death. Genshin Impact really took a wild turn in Inazuma, and who knows what else is yet to come.