Social Engineering chooses bunch of people based on some algorithm and puts them into groups. One of the groups the protagonist belongs to is Tau and its the chosen one by its creator. Like every other "we are special snowflakes and we are slowly taking over positions of power" story (similar to religious institutions, conglomerates etc), the affinity groups start their movement. 
 And it bites them in their collective asses. And the protagonist gets kicked out of his affinity cause how dare he save his step-brother from cheesy villains! Oh and there is some global thing going on where China, India and Pakistan are involved. 
 The story line a serious version of "Mean Girls" or any high school clique gone global.