When you hear of a home invasion, the words likely conjure a scenario in which one or more people enter a home forcibly, seeking to rob the inhabitants and perhaps relieve them of their lives. And you’d be right. Such home invasions are rare, rare enough that when something like that appears to have occurred, law enforcement is generally suspicious of the story from the get-go.But there are violent home invasions bent on robbery and murder, and then there are invasions of a home’s peaceful space by increments, in which a guest is invited willingly, but they bring unwelcome others and others, and still others, until a home is invaded by a horde of unknown and hostile squatters. Either scenario can be dangerous...