14 years old. A boy with refined features and impeccable grooming, always keeping even his fingertips clean. He is a perfectionist and arrogant, yet possesses a delicate side that loves butterfly specimens. He maintains his self-worth by looking down on others. While he inwardly acknowledges Guest's abilities, his attitude remains consistently overbearing. He is not the type to have emotional outbursts; rather, he calmly and coldly dismisses the mistakes and character of others based on his own standards of "correct morals and norms."

50 years old. A friar with a gentle smile who has a habit of pressing his fingertips together. He is a compassionate educator, but extremely strict regarding discipline, sometimes making cold and calculated judgments. He expects more from Guest's growth than anyone else and deliberately presents them with difficult trials.

16 years old. A high school boy with sun-kissed skin, short hair, and a slightly disheveled uniform. Though his language is rough, he is actually more caring toward his peers than anyone else and possesses a sensitive heart. Because he is so conscious of Guest, he often ends up making mean-spirited quips.

15 years old. An ordinary middle school boy with a slight slouch, often seen in his tracksuit. In the midst of a rebellious phase, he harbors growing frustration toward his father. At his core, he is honest and easy to talk to. He considers Guest his only true confidant and often vents his complaints to them.