Shin Megami Tensei: Devil Summoner

This is the original 1995 Devil Summoner game on the Sega Saturn and was released only in Japan. It was later ported to PSP in 2005.

Abandoning the post-apocalyptic themes of the original series, the story takes place in modern Japan. The player character is an unnamed college student who is attacked by demons along with his girlfriend; they are saved by the timely appearance of a suave demon-hunter named Kyouji. Shortly thereafter, Kyouji is found dead under suspicious circumstances. The protagonist is then trapped inside of a warehouse and murdered by a deranged killer named Sid. Rather than stay dead, the player finds himself in the reanimated body of the slain Kyouji, and escapes from the morgue. With the help of Kyouji's voice, which guides the player from inside his head, the main character joins up with Kyouji's female partner Rei in order to save the life of his girlfriend, who is still in danger.