Adjective. It means, 'to be a waste of time', or 'a waste of space'. Also, if you use Danmar you describe a male being, it can mean, 'heartthrobbish freak'.
1)I don't want to be a Danmar talking to you.
2)That girl is such a Danmar- she never talks to anyone.
3)I can't believe he's a Danmar! He fooled me once, but he'll never fool me again!