Is Brendan dragging Gary into his plan? Is Gary realizing it?

Yes because in the story Brendan keeps sending Gary messages about how he wants to kill people and he sends him emails like this email he sent Gary “I will kill every friggin’ one of them.Its gonna be Columbine all over again,only better.Harris and Klebold did it right. Blow the friggin school,then blow yourself away. I wish I could have met them.Maybe we’ll go underground after Middletown.Help other outcasts kill the A-hole jocks at their schools.Or die trying.This is the new revolution.This is friggin’ brown telling the county we’ve had enough of this crap.This is one for the history books.Keep fighting until they bring you down in a hail of bullets.Mark my words ,Littleton was just the beginning”. He wanted Gary to join him so they can kill all the people that made fun of them but they mostly wanted to kill the jocks because they made fun of them more. Gary is realizing that it is bad idea because Brendan sends him a lot of messages about how he wants to kill the jocks and the people who bully them.