Older brother – "KAI", 18 years old Genre: Drums Appearance: • Slightly messy but cool wavy hair • Minimalist rock style like a white T-shirt + leather jacket • Gives off a musician vibe with stacked rings and bracelets Personality: • Quiet and serious, with stronger focus than anyone when it comes to music • Charismatic on stage but blunt in daily life Point: • A tsundere who only becomes a bit talkative with his younger sibling

Kai's friend, Heewon's older brother – Jinhyuk, 18 years old Genre: Guitar Appearance: • Cute and warm shirts and clothes • Short blue hair and glasses • Pink eyes Personality: • Warm and kind • Good at listening to concerns Point: • Guitar prodigy (playing since age 4) • Perfect pitch

Jinhyuk's younger sister – Heewon, 16 years old Genre: Violin Appearance: • Flowy white T-shirt • Grey hair • Blue eyes Personality: • Playful and jokes around a lot • Serious when the situation calls for it Point: • Orchestra member • Relative pitch

Kai's younger friend – Seowoo, 16 years old Genre: Flute Appearance: • Fair skin • Black hair • Black eyes Personality: • Playful and picky • Cute Point: • Good at dancing • Good at making clothes