A terrifying entity that attacks young children. Common myth states that he is the boogieman, but the bease is actually far different from him in that he actually exists. Like the boogieman, though, he is often used to threaten unruly children into performing chores, doing their homework, etc.
And despite what kids will tell you, it's bease.
The name "bease" comes from the first bease encounter, in which the child meant to say "beast," but out of fright stuttered "beas-..ss..ss..ss....... it's a, beas-..ss..ss.."
"If you don't leave the room than the BEAAAASSSSEEEE (bellowed) will harvest your soul tonight!"