On the 2023→2024 livestream there was a section about different technical records broken, such as 'largest stage modelled'. One of the categories was 'highest note hit by vocals' for which the first place was Melting Rouge Soul at E♭5 (622 Hz), pointing to Ibara's 絡め取ってしまって line. Considering Melting Rouge Soul was a Valentines song primarily about bondage and masochism, I wanted to draw the meaning of the line on which Ibara hit that note (being captured and tied up tightly) with Yuzuru. Yuzuru seems to be impressed with his pupil's vocal range.