And then he can begin inquiring into their true names. It seems just crazy enough to be true and if it is true, does one lead them or are they more of a cohesive unit? Let's say they do have a leader and there is one Joker that reigns supreme.
Many comics have said that Sans is the older brother... But I haven't gotten any proof yet. It makes sense that Sans could be the older brother... But it makes just as much sense that Papyrus could be the older brother.
Though she prefers Undyne, her dialog suggests that she may also have intrest in the player. And we are gay as well, by dating Papyrus. If we are a girl: Papyrus and Sans are clear. And Alphys is still lesbian, and always will be due to her love for Undyne. Genders not a thing?: So if that were true, why would they lable characters with she or he.