Going out on dates or otherwise occupying someone's boy or girlfriend so that said someone can get on with their lives.

Date-Sitter - the sucker stuck acting as a buffer between two such people in a dying relationship.
He was driving me nuts, so I talked one of my sorority sisters into date-sitting him for a few weeks until I'm more firmly attached to Bruiser here.
by marfita May 28, 2010
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