The kind of girl (usually a girl, but sometimes a boy) who is a total tomboy, confident, loves animals and owns like three dogs. Usually has blue house, most Mel's are really Melody, Melanie, or Melissa's who have decided they don't want a cutsie name that means "red rose" or "honey bee".
Mel's are awesome, and Kompelien's are even more awesome, so if you know somebody who has both names be nice to them and get to know them; they'll really help you out in the future when no one else will.
"Oh, look at that new girl!"
"Oh, she's awesome. A total-tomboy, too."
"Ah she must be a Mel."
"Not just any Mel, she's a Mel Kompelien."