When used in referance to one's self, a scaj is just a synonym for butthole.
"...Mom, they felt me up, they tried to look in my scaj."
It is obtained primarily from rubbing one's anus on the sidewalk, but can also be obtained in other ways such as a rough night or a dirty game of hide-and-seek.
When one refers to theirself, a scaj is a synonym for butthole.
"Mom they checked everywhere, they even looked in my scaj!"