A bowel movement (typically at least partially formed) that causes smoky looking steam or vapor to rise from the bowl. The visual is similar to a creature in a foggy bog or marsh in a sci-fi or horror movie.
I am never going to another one of your barbeques. All that Natty Ice, and chili, and hot wings had me birthing a bog monster the next day.
by Fazed-NB October 18, 2006
Get the bog monster mug.
-A bog monster is a hidious creature from the bog, that reaks like shit, and has a bog eye.
-You can also call taking a dump, having a bog monster, because it smells like a bog monster.
-I just released a bog monster in the bathroom, you might want to wait a few minutes before going in there.
-That bog eyed monster smells like the dump john just took.
by Al Gettin' Stacks July 6, 2011
Get the bog monster mug.
A term used to humiliate a person who has a sick fetish for poo, can also be used to humiliate a person who either gives or receives anal sex.

Can also be used in first person tem to describe one's self.
"yo, sam over ther is the biggest bog monster, he did shelly and nadia in the ass last night"

"man, im the biggest bog monster ever. I just enjoy anal to much"
"yer you are a hugh bog monster"

by Matthew & Jessica November 21, 2007
Get the bog monster mug.