Maniac has decided that he's causing the Beale family too much hassle. He hasn't done anything to them, of course, but a white kid in a black family raises the hackles of many people in the racially-divided town of Two Mills.
Their hate-filled attitude is expressed by the willful destruction of Amanda Beale's prized encyclopedia Volume A, a book that she loved to read a lot. Maniac knows that whoever did this was sending a message that he should not be living in a black neighborhood and that he should go back to his own.
The last thing Maniac wants is for the Beale family, who've been so good to him, to get hurt on his account. So he decides to leave Two Mills. He does so by walking straight down the middle of town along Hector Street, the dividing line between the East End and the West End.
As Maniac walks right along the middle of the road, he's harassed by traffic as well as rival gangs on both sides of the racial divide, each of which calls on him to come over. Collectively, they form a kind of escort for Maniac as he walks down the dead center of Hector Street and out of Two Mills.