A black sheep is a biting beast.

The mountain sheep are sweeter, But the valley sheep are fatter. We therefore deemed it meeter To carry off the latter. - Thomas Love Peacock,

Your sheep, that were wont to be so meek and tame and so small eaters, now, as I hear say, be become so great devourers, and so wild, that they eat up and swallow down the very men themselves.

I'm the black sheep.

A leap year Is never a good sheep year.

She walks--the lady of my delight-- A sheperdess of sheep. Her flocks are thoughts. She keeps them white; She guards them from the steep. She feeds them on the fragrant height, And folds them in for sleep.