"Thou wilt look well," said Don Quixote, "but thou must shave thy beard often, for thou hast it so thick and rough and unkempt, that if thou dost not shave it every second day at least, they will see what thou art at the distance of a musket shot."
There are no more uses of "unkempt" in the book.
Show samples from other sources
This kid has long, unkempt hair and a hardened look about him.
Neal Shusterman -- Unwind
With his dark unkempt hair, his unlined face, he looked no more than twenty-five.