Mogu Japanese Food is a Japanese restaurant on Maria Place in Ohura, in the Ruapehu district of the Whanganui region, holding a 4.8 rating from 20 Google reviews. Its online presence is a Facebook page rather than a website, so it is worth checking there or ringing ahead before the drive.
A good Japanese kitchen lives or dies on the basics: rice seasoned and cooked properly, a real dashi, and fish or produce that shifts with the day rather than a fixed menu that never does. Rural and small-town kitchens in New Zealand often run this way, with a short menu done well beating a long one done thinly. Regulars ask what came in fresh that day, go easy on the soy, and give the slow, simmered dishes as much respect as the raw ones.
For Japanese cooking out on the Ruapehu back roads, Mogu is Ohura's local table.