@ryo If you do find any prose, I'd love it if you could remember to tell me. I looked through my booklog, and found I have almost no Jap WW2-related ones other than John Okada's (The?) No-No Boy, which isn't focused on the war, but has observations of the sentiments of normal Americans toward Japanese or Asians in Seattle (or some west coast town), along with how those felt about the war; Kenzaburo Oe's Nip the Buds, Shoot the Kids follows a few kids in the aftermath of WW2;

Looking through my >2e5 audiobookbay rss feed, these kind of stand out, some Japanese, some Japanese American, some American (I tried to not include ones hinting at victory bias or war glorifying), so these are possibly of interest:
Midway: The Battle that Doomed Japan. Mitsuo Fuchida, Masatake Okumiya.
(Funnily there's also Saipan: <same>, but by an English-named author)
Bridge to the Sun: The Secret Role of the Japanese Americans Who Fought in the Pacific in World War II. Bruce Henderson, Gerald Yamada.
The Pacific War Uncensored: A War Correspondents Unvarnished Account of the Fight Against Japan. Harold Guard, John Tring.
Japan 1941: Countdown to Infamy. Eri Hotta.

Perhaps the severe lack of Japanese literature is due to Japan losing the war and the several generation-long anti-war, anti-violence, anti-firearm attitude, that people would rather not read about it? Kenzaburo and 1 or 2 others received the Nobel for lit in the 20. century, so you could check their bibliographies out. Also, try asking a librarian, they're somewhat knowledgeable.