Tobias is a stern and intimidating eighteen-year-old who helps train Dauntless initiates and becomes Tris’s love interest. He’s aloof and strict with the trainees, and he often singles Tris out for critique, but as the book progresses it becomes obvious that he cares about her. He respects Tris’s bravery and encourages her to be her best self. When he nicks her ear with a knife during target practice and yells at her in front of the other initiates, he does so to help her stay strong in front of her competitors. He tends not to explain his reasoning until after Tris confronts him, however, so his behavior can seem manipulative at times.
Tobias disapproves of how violent Dauntless initiation has become, and he pushes back against Eric’s brutality by offering trainees the option of conceding during the fights. He also shows his tender side after he rescues Tris from Peter’s attack, and he gradually grows closer to her both emotionally and physically. Though he admits he struggles with kindness, a number of clues help readers deduce he’s from Abnegation: his dorm wall says “Fear God alone,” suggesting he’s religious like many Abnegation families, he has a short, plain haircut, and he repeats an Abnegation lesson about using guilt as a tool that Tris has heard many times. Indeed, Tris eventually learns that his father is Marcus, an Abnegation leader. Marcus physically abused Tobias throughout his childhood, and this abuse probably contributed to his brooding personality and aloof behavior.