This is a question for anyone who can answer it, but I suspect Note! might have a clue. (Or Yano-san himself?)
Most kanji do, as you know, have a kunyomi (Japanese) and an onyomi (Chinese) reading. But is there any way, or rule of thumb, as to which reading is the appropriate one in a certain instance? Can you make it out from the position in a sentence or other factors?
Take Rei Yano's song title for example...
懐かしい都市
natsu-kashii toshi
The first kanji is natsu(ku) in kunyomi. Then follows the kashii suffix in hiragana. (Speaking of which, what does the suffix mean?)
Then follows, in onyomi, to and shi both meaning city in slightly different ways. I somehow get the feeling that it's rather Chinese to form words by joining similar signs in that way. Is that a useful rule of thumb?
Thanks for your time. 
