Nagi is the first to notice and acknowledge Haruka when HE★VENS and ST☆RISH come across each other, although he first mistakes her as ST☆RISH's manager. He is later corrected by Ajiima Cecil by saying that she is their composer. He sounds surprised to hear that she was the one who wrote their song. When they meet again right before the start of the concert battle, he doesn't have any complaints should Haruka become their composer, and even offers letting her watch their rehearsal. He seems to have acknowledged Haruka's talents as a songwriter, going so far as saying that ST☆RISH does not deserve Haruka as their songwriter.
Eiichi lightly reprimands Nagi once he started acting rather rude towards ST☆RISH, although Nagi protests. It can be assumed that Nagi respects Eiichi as their leader and as someone older than him.
Nagi seems to be closest to Kira the most among the three of them, as shown by how Nagi often looks to Kira for comments and the like.
Nagi thinks that ST☆RISH is less talented the HE★VENS and ridicules them at every chance he gets.