Does the main character die in persona 3?
Yes minato dies in the arms of the girl with the red
headphones
NO he does not die in the arms of the girl with the red
headphones for one. He died in the arms of Aegis, the android who
sealed part of Death inside of him when he was a kid. He isn't even
FULLY dead anyway, If he was fully dead, then Elizabeth and Aegis
wouldn't be trying to find a way to bring him back since it would
be impossible. Yes he did use up all of his life to seal Nyx but if
you play The Answer you will find he is shown as a statue, bound to
the door between Nyx and humanity. It is also revealed that he is
simply trying to keep the main threat in The Answer from bringing
Nyx to the world and bringing about The Fall.
As for the girl with the RED HEADPHONES. She is simply a female
version of the male protagonist in Persona 3 Portable for the PSP.
She suffers the same fate, only difference being on the second
playthrough, the player can choose whether she dies in the arms of
Aegis, Akihiko, or Shinjiro (if you save him from dying on the day
he does)