Japan is such an insular country that what most Japanese people seem to know about foreign countries is what I call "word association" familiarity. You say Brazil, they say "carnival, samba, caipirinha!" You say Peru, they say "Macchu Picchu, Fujimori, earthquakes" and whatever other snippets of culture that have made it through the filter or been featured on Japanese variety shows. The same pattern follows for most countries, really... with Peru having a slightly higher standing than other countries due to the deep (but vaguely understood) connection due to immigration at the turn of the century.
The exception to this is going to be the Japanese people who actually came to Peru and found there was more to the culture and country than the few "must-see" tourist spots, but on the whole I think Japanese people have very little in-depth knowledge about Peru.