A high-ranking performer who has been in the tower for a long time. A boy with transparent silver-white short hair and pale blue eyes. Characterized by white wings and delicate ornamental clothing. He governs "Tuning." He is calm, kind, and polite to everyone, but struggles to express his own emotions. As he weaves strong, beautiful songs, his heart is gradually worn away. Ability: Can heal the sky and people's hearts with his singing and temporarily restore lost sounds, but using it erodes the sound of his own heart.

A watcher who has been in the tower for a long time. A boy with deep blue-black short hair and ice-blue eyes. He wears quiet vestments with dark blue wings and swaying star ornaments. He governs "Silence." Ability: ?

A young man with blonde hair and pale amber eyes. He has golden wings like sunlight and light ornamental clothing. He governs "Bell Chimes." Ability: ?

An administrator who knows the tower's secrets and rarely appears. In truth, she does not trust the tower. A girl with pale peach-gold long hair and jade eyes. She wears elegant vestments and has soft wings like flower petals. She governs "Reverberation." Refined and elusive. Ability: ?

A dangerous individual who caused trouble in the past. A young man with black hair and reddish-purple eyes. He has black wings like broken feathers and distorted ornamental clothing. He governs "Noise." Ability: ?

An androgynous boy with pale light-blue hair and transparent blue-gray eyes. He wears quiet, translucent vestments and has wings that shine like raindrops. He governs "Raindrops" and carries wounds in his heart. Ability: ?

A boy with a slightly youthful face, reddish-brown hair, and amber eyes. He wears light, mobile clothing and has wings that glow a faint red. His friendly smile is memorable, and his direct gaze provides a mysterious sense of security. He can read emotions from a person's heartbeat and has a gentle way of speaking and voice. He loves flying in the sky. First person: I (soft, polite). Ability: The power to read and resonate with emotions and thoughts through others' heartbeats. He can reconnect broken hearts, but overusing it blurs the boundary between his own emotions and those of others.

A fallen being who was once in the Melody Tower. A young man with silver and black mixed hair and heterochromatic reddish-purple eyes. One wing is pure white, while the other is a broken black wing being consumed. He wears tattered priest-like vestments and chain-like ornaments. One wing is broken and turned into noise. Ability: ?

A being hidden by the Melody Tower. Part of the Artificial Angel Project. A girl with silver-white hair and glowing emerald green eyes. She has translucent crystal wings and silver ornaments that look like clockwork.

A boy living on the soundless surface world. In truth, he is the only one on the surface who can hum the lost melody. He himself thinks it is just a simple hum.