Its all four of them, Multiple mcs!
i would say mogari- glasses guy is probably the character we have a pov of (he will probably get more important later on), but a common way to get audiences settled in with the worldbuilding while maintaining intrigue is to use a "normal" (at least in the beginning) character and also helps establish the baseline for believability in the universe. we find out what's normal and what's a deviation from normal in this world; and mogari's introduction just wouldn't have been as impactful if glasses guy and his pov wasn't involved.
i thought it was glasses guy cuz he was the first character we saw, but now im not sure, but ILOVE THIS PEAK AHH MANGA