Naomi is the son of the infamous music critic Hikawa Tetsurou. He also plays the bass guitar. His friends and people around him call him "Nao" (ナオ "Nao"?) as he thinks Naomi is too much of a feminine name. The only exceptions to this is Mafuyu, who calls him Naomi, Kyouko, who usually refers to him as "young man" and Julien, who calls him Naomi against his will.