The Boxtrolls is a wonderful children's story that, among other things, show kids how awful it is to stereotype and scapegoat others.
Boxtrolls starts with a scenario that sounds a lot like many other dystopias. The above ground society, the Cheese Bits, are terrified of the underground society, the Boxtrolls.
The Boxtrolls literally live underground; They eat insects and use odds and ends from the world above them to make things like a music maker. A manhole is a portal to and from worlds.
Because they are terrified of the Boxtrolls, the Cheese bits and their secret police, the Red Hats, hunt the Boxtrolls as monsters. The White Hats, who govern the Cheese bits, support the Boxtrolls hunts. One of the Cheese bit, a baby, was kidnapped and killed by the Boxtrolls. But was the Trubshaw baby really taken?
Eggs doesn't think so. He knows the Boxtrolls aren't monsters. Eggs knows this because he lives with them, They are his friends who assure him his peach skin is fine even though theirs is green or grey.
Eggs feels ok about his appearance until a girl who lives above ground, Winne Portley-Rind, calls him a name he never heard before, "boy."