Since the student's pursuit of dominance is realized through other students in the class, it can affect the formation of relationships with surrounding students. In order to understand the role of other students in the behavior of the perpetrators, it is necessary to analyze and understand the relationships that are going on in the classroom on a daily basis. In this study, we investigated how this peer structure is located and interacts in the peer ecosystem by comparing the students who perpetrators of school violence with the other students. For the purpose of this study, the peer ecosystem surrounding school violence was modeled as a network problem, and a two-level exponential random graph model was applied to estimate the friendship between the perpetrators and other students through statistical estimation of network configurations. As a result of the main analysis, first of all, the perpetrators take strategic actions to keep other students close and to keep away from other perpetrators. Because of their friendship with the aggressor, other students are limited in their friendship with the other students. There is a limit to forming friendships with other students. Victim students are the target of friendship with other aggressors or students, and are excluded by other students. These results suggest that the roles and divisions of other students are not fixed by psychological characteristics, but may vary depending on the friendships they have in their daily life. In addition, for the prevention of school violence, it is necessary to investigate the friend relationship with other students who reinforce or compensate the bullying student's behavior through a case-by-case approach centered on the ego network of the aggressor, victim, and other students.