In the Japanese version's commentary with the game's composer Masaharu Iwata, he stated that the title for "Back Fire" is actually “Chotto Otona no Daakuman” (“A More Mature Darkman”). A few years prior for the game Tactics Ogre: Let Us Cling Together, he composed the last boss theme named “Darkman Abikyoukan” (“Darkman Pandemonium”), which he described as an "up-tempo, kind of insane sounding song" on a level of madness that "Back Fire" couldn't quite reach, hence the title.
Contributed by ProtoSnake