So my novel, which will be written in English, will be set in Japan, with Japanese characters. I only know a little about the culture, and I do not speak Japanese. My question is: is is a good idea to employ Japanese honorifics (name suffixes), or should I omit them? My main character's father, for instance, is the clan's chief, and his son addresses him with respect. So should he say "Hello, father," (instead of the american informal "dad"), or should he say the title in japanese, "Hello, okasama,", in result mixing the two languages? Others will be talking with the clan chief, too. Somehow, Tomura-sama sounds more "right" than "Master Tomura", or "Chief Tomura". In fan fiction there is often a mix of the two languages with the use of Japanese honorifics. But I don't know if this applies to serious literature. Also, I cannot think of my main character calling his teacher anything other than Sensei... Thoughts???
You might consider reading Martin Cruz Smith's Arkady Renko novels. I'm not that familiar with Soviet (or post-Soviet) society, but he had me convinced it was taking place in Moscow, et al. Or, closer to what you're doing, Rising Sun by Michael Critchton.
I think a mix would be great, it would capture the mood and feeling of Japan, but try not to go overboard with fancy words we may know nothing of. If you do, make sure to use them in a context that may make the reader feel smart for immediately figuring it out, or at the very least, make it obvious.
Read the novel Shogun by James Clavell. It beautifully does what you're trying to illustrate. Use this book as an example. If you want the setting to be convincing, you need to become familiar with the culture and do the necessary research.
I think that Japanese honorifics somewhat change from period to period. So if you want to get them right you have to know in which period your story will unfold. (The Heian, the Edo, etc.). Better consult with a Japanese person somewhere along your way. I think your approach is best. Using some honorifics and maybe some other Japanese words that are used commonly, fleshes out their culture more. But use them mostly in dialogue (at least the honorifics) because in narration they don't make sense (even if the story is in first person). And for gods' sake mate! Never "dad"! (Even in private conversations some honorific limits should be kept, especially if the dad is a clan's chief. Even in narration). Simply put "father".
