It can be shouted to express anger, or stated simply to baffle someone. It can also be used when describing one's exploits in the bathroom. Many variations can be added to wreeuh, all of which involve sounding like a retarded cave man. A favorite combination of the word is "oodles wreeuh!"
"Wreeuh! Wreeuh wreeeuh? Wreeeuh huh!"
- to baffle people
"Wreeuh! I just got my cock stuck in the blender again! Wreeuh wreeuh!"
"That was quite a wreeuh I just took ... I've never seen a toilet catch fire before.