Inaba was out on a date with his girlfriend (he had several; this particular one was girlfriend #4) on March 17th, and was shot from behind by Izumi, and summarily died.
Even in critical situations, he seems completely unmotivated except for when it comes to girls, even hitting on Reika during battle. It seems that all that runs around in that head of his are women — hooking up being his driving force.
When Reika was in a crisis, he eventually decided to take up arms to fight, but even then, it might have only been to appear that he was trying to be valiant, trying to show his cool self, and defending the “damsel in distress.”
Inaba later participated in the second half of the mission and saw Kurono in battle, and was astonished by his prowess and strong will to survive and prosper — something that Inaba lacks completely.
Though he was a womanizer and generally a lout, being around Kurono helped Inaba to build his resolve and become better; rather than exact feelings of jealousy or conflict, Inaba gradually changed, not only to respect Kurono, but to strengthen the will of himself.
Compared to Kurono and Suzuki, who play very active roles and adapt quickly to extreme conditions and environs, Inaba could be seen as a relatively realistic character, one that readers might associate with, as an “everyday average guy,” who persists against odds and adapts, and even flourishes to some degree.
--- Oku-sensei’s comment:
Admittedly, I have thought, “Wait, why’d I put this guy in the story?” and also thought that the story would remain functional with or without the introduction of this character.
(laughs) But, it was either that or add yet another profoundly dashing, handsome guy, so I just went ahead and made him.