Someone who is so useless that they can be compared to a crum of bread. A crum is someone who resides in their house all the time and refuses to participate in any galas or events.
Mike "Hey Dom lets go get that chick to come over tonight to my crib"
Dom "Not even worth it bro, that girl is a crum, she ain't leavin her house for a million dollars"
A noun for crusted cum on skin.
Referred to male and/or female cum left on the skin as it crusts.
As the cum dries it leaves little crumbs referred to as crum.
Renato came on my face last night. I totally forgot about it and it turned into crum. I still ate it.