Arlo is  a fourth-year student of Wellston High, and the third ranked student in Wellston. He is also the school's King and strives to maintain order in Wellston. He has with wavy blonde hair, angular blue eyes, "angry eyebrows", and small light-blue stud earrings. He is very tall, towering over nearly all of his classmates except Holden. He is seen wearing a Wellston school uniform during school hours. 

Arlo is known for being very authoritative and domineering. He displays a lot of leadership characteristics and remains cool, calm, and collected in various situations. Almost nothing fazes him and he isn't very impulsive. However, his arrogance, manipulation, and cunning nature often makes him dislikable, to the point where readers refer to him as Asslo. In addition, he has a serious fixation on the hierarchy and people abiding by it. He has also been shown to go to extreme measures in order to maintain it. Furthermore, he displays a lot of apathy when it comes to bullying pertaining to the lower tiers, as he deems it normal, all in the name of their social order; hierarchy. Lastly, Arlo is loyal and somehow empathetic only when it comes to the affairs of the royals or his friends.