Unicorns mate for life, and the pairs generally make their homes in specific glades or dells within the vast forests they protect (these regions can cover anywhere from a few dozen square miles to hundreds). They allow good and neutral creatures to pass through, hunt for food, or reside in their woods unharmed, but evil creatures and those who damage the local ecosystem more than necessary through sport hunting or commercial logging are swiftly driven out or killed. On rare occasions, lone unicorns without mates or whose partners have been slain have been known to adopt young women of exceptionally pure virtue as surrogates, allowing the women to ride on their backs and becoming their guardians and protectors for life. This bond generally ends amiably if the woman becomes more committed to someone else-such as a lover or child-giving rise to the myth that unicorns only befriend virgins.